This section is limited to single-word palindromes only. I appreciate contributions to this page, but I am not including sentences or phrases which are palindromes, since there are other websites which list large numbers of them. Principal contributors to this section are Dan Tilque, Stuart Kidd, Philip Bennett, Charles Turner, and Paul Wright.
TATTARRATTAT is the longest palindrome in the OED2, which calls it a nonce word. The OED2 shows a single use in 1922 by James Joyce in Ulysses: "I knew his tattarrattat at the door."
KINNIKINNIK is the longest palindrome in W3. The OED2 shows these variant spellings: kinnikinnic, kinnikinnik, killegenico, kanickanick, kanikanik, killickinnick, kin(n)ikin(n)ick, -kineck, -kennic, kinnakinnec. Audubon L. Bakewell IV reports the word is usually spelled kinnikinnick. The OED2 defines the term as "a mixture used by North American Indians as a substitute for tobacco, or for mixing with it..." or "any of the various plants used for this, as the Silky Cornel, Cornus sericea, Red-osier Dogwood, Cornus stolonifera, and esp. Bearberry, Arctostaphylos Uva-ursi...." The word is derived from an Algonquin word meaning "mixture." Handbook of American Indians North of Mexico, Frederick Webb Hodge, 1907 & 1965 gives the variant spelling KINNIK-KINNIK, which is an even longer palindrome, and a "repeater" if the hyphen is ignored [Stuart Kidd].
DETARTRATED is listed by Guinness, where it is described as "a contrived chemical term." However, the word appears in several Internet pages on Concord grape juice and even once or twice on apple juice, including the page http://www.nysaes.cornell.edu/hort/faculty/pool/herbbarber/herbgage3. htm which has this paragraph:
Concord contains potassium salts commonly called tartrates that won't filter or centrifuge out. Must be allowed to settle out by gravity - minimum of 6 weeks, before it's detartrated and ready to use. Otherwise will have sediment in the bottom of the bottle of juice and the jelly will be a little grainy.Detartrated is said to have been coined by Dmitri Borgmann.
DETANNATED appears in a work on plant extracts published in 1892. It shows two detannated concoctions, detannated elixir of calisaya bark and detannated elixir of cinchona. The text can be found at http://chili.rt66.com/hrbmoore/ManualsOther/ElixForm.txt According to the Palindromicon, "detannated tincture of cinchona" appears in the 8th revision of the Pharmacopoeia of the U. S.
The longest palindromic taxons are AFGOIOGFA (a genus of hymenopterans), AIDEMEDIA (a genus of Hawaiian finch), and ALLENELLA (a species name for a moth, Oecophoridae Bibarrambla allenella as well as a type of mollusk and a hymenopteran [Susan Thorpe, Charles Turner].
The longest palindromic genus-species combination is ORIZABUS SUBAZIRO (a species of scarab beetle). Other palindromic genus-species combinations are AHA HA (a sphecid) and XELA ALEX (a species of syrphid fly).
Palindromic place names include ANAHANAHANA (Madagascar), KANAKANAK (Alaska), KINIKINIK (Alberta), NUTUTUN (Mexico), NEUQUEN (a river, province, and city in Argentina), and WASSAMASSAW Road (near Summerville, South Carolina). The northernmost palindrome is QAANAAQ (the administrative capital of Northern Greenland). A list of palindromic place names from the 2000 U. S. census is here.
GLENELG is one of the most common palindromic geographic names worldwide. The original is a village in Scotland. There's also a town in Maryland, a suburb of Adelaide, South Australia, a village in Nova Scotia, and a township in Ontario. Because there was a Lord Glenelg (the only one with that name) who was the British Colonial Secretary in the 1830s, the name is on various other features, such as streets and rivers, in Australia and New Zealand. At Glenelg High School in Maryland, the yearbook is the Palindrome. Glenelg is also a place name on Mars.
AKASAKA is a district in Chuo, Tokyo [Joseph Hernandez].
Common everyday English palindromes (including a few very common abbreviations) are A, AHA, BB, BIB, BOB, BOOB, BUB, CIVIC, DAD, DEED, DEIFIED, DENNED, DEWED, DID, DUD, DVD, EKE, ERE, EVE, EWE, EYE, GAG, GIG, HAH, HUH, HUH-UH, I, KAYAK, KOOK, LEVEL, MA’AM, MADAM, MOM, MUM, NOON, NUN, PAP, PCP, PEEP, PEP, PIP, POOP, POP, PULL-UP, PUP, PUT-UP, RACECAR, RADAR, REDDER, REFER, REPAPER, REVIVER, ROTATOR, ROTOR, SAGAS, SEES, SEXES, SHAHS, SIS, SOLOS, SOS, STATS, TAT, TENET, TIT, TNT, TOT, TOOT, TUT, TUT-TUT, WOW, and ZZZ.
Common personal names include ADA, ANNA, ASA, AVA, BOB, CEC (for Cecil), ELLE, EVE, HANNAH, LIL, NAN, OTTO, VIV, and VYV.
REDIVIDER is the name of a Canadian band. The word does not appear in the OED2 and an Internet search in March 2000 failed to find a single use of the word, except for its appearance in lists of palindromes or as the name of the band.
RELEVELER is the name of a rock band. However, the word is not found in the OED2 and does not appear to exist on the Internet except as the name of the rock band or as an example of a palindrome.
DELEVELED is used in fantasy role playing games to indicate that a character has lost a level. Several usages with this meaning can be found on the Internet.
Long coined palindromes which do not appear in dictionaries and for which no usages have been found in Web searches include DEGARAGED, DEROTATORED, DEROTORED, DESUFFUSED, REGARAGER, REROTATORER, REROTORER, and RESUFFUSER.
The Hebrew alphabet has three palindromic letter names: MEM, NUN, and WAW. A variant spelling of waw is VAV and a variant spelling of another letter name, teth, is TET.
KRK is a Croatian island [Juozas Rimas].
SOS by ABBA was a hit recording with a palindromic title and artist. Palindromic album titles include Ole ELO by the Electric Light Orchestra, LIVE EVIL by Black Sabbath and by Miles Davis, EVIL LIVE by The Misfits, UFO TOFU by Bela Fleck and the Flecktones, AJA by Steely Dan, and AOXOMOXOA by the Grateful Dead. AHA is a Norwegian pop group.
Palindromic drug names include XANAX, RAXAR, LEXXEL, LOZOL, and MERREM [Dennis Miller].
YREKA BAKERY is a famous palindrome, the name of an actual bakery in Yreka, California, which closed in the early 1960s. There is now a deli with the same name. An art gallery named yrellaGallery was later located next door to where the bakery formerly stood, although in 2005 it was reported to be closed. An album titled Yreka Bakery was recorded by a band called Pep Squad. Mark D. Lew wrote in 2001, "About four years ago, on a road trip up I-5, I made a point of stopping in Yreka to look for the famous deli. It was Sunday evening, so it was closed, but I can attest that it does indeed exist. On Hwy 24, between Walnut Creek and Oakland (where I live), there is a building with 'Elite Tile' displayed in large letters, easily visible from the freeway." Dan Tilque provides the name of a refiner in El Dorado, Arkansas, LION OIL.
REGAL LAGER is a corporation headquartered in Kennesaw, Ga., as well as a brew of beer [Mike DiCola].
In Swedish, NATURRUTAN ("nature square") is the title of a nature TV program. And a somewhat contrived palindrome in Swedish is PORTUGALRALLARLAGUTROP ("Portugal"=the country, "rallarlag"=a team of navies, "utrop"=exclamation, outcry) [Fredrik Viklund].
LON NOL (1913-1985) was a general and political leader in Cambodia.
LEON NOEL was born on Christmas Eve in 1908 and became a child celebrity in his hometown of Valparaiso, Indiana. He was included in Robert L. Ripley's Ripley's Believe It or Not. Noel lived most of his life in St. Petersburg, Fla. He died in Largo, Fla., on Christmas Day 1999.
ROBERT TREBOR (1953- ), born Robert Schenkman, is an actor [Robert Sanders].
ANUTA CATUNA (1968- ) won the New York City Women's Marathon in 1996. [Joshua Spodek].
Ramon LLULL (fl. AD 1300) was a Catalan mystic and poet whose writings helped to develop the Romance Catalan language and widely influenced Neoplatonic mysticism throughout medieval and 17th-century Europe. He is also called Raymond Lully.
Dr. Darold TREFFERT is the world’s leading expert on Savant Syndrome.
Anthony OGOGO is a British boxer [Paul Wright].
OXOBOXO (a small lake in southeastern Connecticut) is a palindrome and also has horizontal line symmetry (Dmitri Borgmann).
GLYCYLGLYCYLGLYCYLGLYCINE has a 19-letter internal palindrome from the first to the last C and another 19-letter palindrome from the first G to the last G [Nick Papuga].
The longest palindromic cluster embedded in an English word is composed of the first eleven letters in SENSUOUSNESS [Charles Turner].
More palindromes of four or more letters follow:
ABABA a genus of beetles
ADINIDA a group of protozoans belonging to the order Dinoflagellata. (W3)
AEAEA the Island of Dawn in Homer's Odyssey
AETEA a marine Bryozoan
AFOFA a Portuguese dance (Funk & Wagnall's New Standard Dictionary of the English Language, 1941)
AIDEMEDIA a genus of Hawaiian finches
AILIA and AINIA genera of fish
AITIA plural of aition, a tale devised to explain the origin of a religious observance. (W3)
AJAJA AJAJA one of various scientific names for the tropical American roseate spoonbill. Also called AJAJA and AIAIA
AKA AKA a rural district near Auckland, New Zealand
AKKA variant of acker, or a pygmy (OED2)
ALALA a Greek battle cry (OED2)
ALLAALLA Hausa (from Rex Gooch, Word Ways)
ALLENELLA a genus of molluscs
ALOMOMOLA is a Pokemon
ALULA the bastard wing on a bird. (MWCD10)
ANANA variant of "ananas", the pine-apple (OED)
ARAGARA a genus of flies
ARARA a genus of birds
ARRAARRA US Indian tribe (from Rex Gooch, Word Ways)
ARRAWARRA a town in coastal New South Wales, Australia (Cambridge Dictionary of Australian Places, Word Ways)
ASSA a genus of Australian frog
BACAB one of 4 Mayan brother gods that hold up the sky. (Encyclopaedia Britannica, 1991)
BEEB informal term for the BBC (OED2)
BIIB a crimson fruit-dove from the Caroline Islands in the west Pacific Ocean
BOOB a foolish mistake or blunder (OED)
BURGGRUB the name of three villages in Bavaria (Encarta World Atlas, Word Ways)
CAMMAC copper halfpenny in use in Ireland in the early 19th century (The Century Dictionary and Cyclopedia, 1911)
CAUAC a day in the Mayan second, sacred calendar
CAYAC an iguana native to the Caribbean island of Carriacou
CILDLIC old form of 'childlike' (An Anglo-Saxon Dictionary, Word Ways)
CINENIC related to cinene, a terpene derived from cineol. (OED2)
DEEDEED euphemistic for "damned" under "dee" (verb) (OED)
DESESED an early spelling of "disseized" (OED)
DEUOUED an early spelling of "devoved" (OED)
DEVIVED rendered lifeless, devitalized (OED)
DEVOVED archaic word meaning devoted or dedicated. (W3)
DIXID one of the Dixidae, a family of mosquito-like insects
DYSSESSYD a 15th-century spelling of diseased, according to Paul Wright
EDIFIDE an early spelling of "edified" (OED)
EEVEE the name of a Pokemon
ELLEMELLE a small community southwest of Liege in Belgium (Encarta World Atlas, Word Ways)
EPEPE a West African tree of the Terminalis genus
ESSSSE old spelling of "ashes" in the sense "dust of the ground" (Hence used to express man's mortal constitution) (OED)
EVITATIVE a grammatical case, expressing what is to be feared and avoided
FINNIF slang term for a five dollar bill. (OED2)
GIRAFARIG the name of a Pokemon
GIPSY’S PIG the hedgehog. (OED2)
GNIPPING given to fault-finding (English Dialect Dictionary]
GOOG Australian slang for egg. (W3)
HADEDAH, HADADAH a large grayish-brown African ibis, with wings tinged iridescent green (W3, OED2)
HAGIGAH particular Jewish sacrifices (W3)
HALALAH var. of halala, a unit of currency in Saudi Arabia (= 1/100 riyal). (W3)
HAQIQAH esoteric truth that transcends human and theological limitations (Encyclopedia of Islam)
HAZIZAH a term connected with the rite of total immersion (Encyclopedia Judaica, 1972)
HO-OH the name of a Pokemon
IGIGI a group of heavenly spirits under the god Anu in Babylonian religion. (W3)
ILLIBILLI a town in the Sudan (Encarta World Atlas, Word Ways)
IMAMI a member of a Shi"ite sect (W3)
JIJIJ a small-leafed tree from the mangrove swamps of the Solomon Islands
JILLIJ the name of a lighthouse in Tunisia (Official Standard Names Gazetteer, Word Ways)
KAKKAK a bittern of the Ixobrychus genus found on Guam
KAZAK Turkic people of central Asia. (W3)
KEEK-KEEK a call used by children in the game of hide and seek [OED]
KILLIK a surname
LEFFEL an obsolete form of "leeful" (OED)
LEHAHEL one of eight seraphim in the cabala (A Dictionary of Angels, Word Ways)
LEMEL metal filings. (W3)
LEPPEL a spoon (English Dialect Dictionary)
LIA FAIL stone on which the ancient kings of Ireland were crowned (W2)
LITTIL a fourteenth-century spelling of "little" (OED)
LOCOL a small bee from the Philippines that produces sour honey and darkish wax
LUFFUL an early spelling of "loveful" (OED)
LUTTUL an early spelling of "little" (verb) (OED)
LYSYL the acid radical of lysine. (W3)
MALAYALAM Dravidian language spoken in SW India. (MWCD10)
MARRAM a type of beach grass. (MWCD10)
MINIM 1/60 of a fluid dram. (W3)
MURDRUM secret murder (W3)
MUTUM the razor-billed curassow, a large arboreal bird of the Amazon region
NAAN a round flat leavened bread of the Indian subcontinent.(MWCD10)
NAURUAN inhabitant of Nauru, a Pacific island nation. (W3)
NEUQUEN a city in Argentina
NIKIN a very soft animal. (OED2)
NIRURIN a constituent of the tropical plant Phyllanthus niruri (Dictionary of Natural Products, Word Ways)
NISIN an antibiotic produced by a bacterium of the genus Streptomyces (W3)
NORURON the chemical C13H22N20. (Dictionary of Chemical Names and Symbols, Word Ways)
OGOPOGO monster supposedly living in Lake Okanagan in British Columbia. (OED2)
OOLOOPOOLOO alternative name of Karanja, an aboriginal language of Queensland, Australia
OOROOROO a creek in New South Wales, Australia
OPPO British slang for a friend or companion (W3)
OTTETTO octet, a musical composition for 8 parts. (W2)
OTTO altered form of "attar", the fragrant essence of roses (OED)
OTTOOTTO 8-8 time in music (from Rex Gooch, Word Ways)
PARAPARAP a town in the state of Victoria, Australia (Australia Map Series Gazetteer, Word Ways)
PEEP-PEEP an imitation of the feeble sound made by young birds (OED)
PEEWEEP lapwing or greenfinch (W3)
PYLYP a surname
QAWAQ a sea lion from the Aleutian Islands or western Alaska
QAZAQ var of Kazak (see above) (W3)
RACK CAR a railroad car having end racks but no sides. (W3)
REIFIER person who regards an abstract idea as a material or concrete thing. (American Heritage Dictionary)
REPPER the common foxglove or digitalis
ROOD-DOOR door in the rood screen of a medieval church. (Catholic Encyclopedia, 1913)
ROTAVATOR trademark for a rotory tiller in the United Kingdom. (OED2)
SANANANAS pale-yellow West Indian crabs (Dictionary of Jamaican English, Word Ways)
SAWBWAS hereditary rulers of a Sahn state of Burma (W3)
SEESEES Asiatic partridges
SEMITIMES an undefined term in W2 but logically meaning 'half times'.
SENONES a Celtic people living in northern Italy (W2)
SHALALAHS a former Indian village on the Umpqua River in western Oregon (Handbook of American Indians North of Mexico, Word Ways)
SIDIS a genus of beetles
SIMIDIMIS Jamaican dances (Dictionary of Jamaican English, Word Ways)
SOBOSOBOS African black nightshades (Hamlyn Encyclopaedic World Dictionary, Word Ways)
SOOSOOS Gangetic dolphins
SPACECAPS a type of collectible trading disks, e.g. Star Trek
SUDUS a genus of weevils
SULLUS a genus of fish
SUNNUS East African antelopes allied to waterbucks
TALLAT a loft over a stable (OED)
TAMMAT as much hay or straw as a man can carry (English Dialect Dictionary)
TARRAT a loft (English Dialect Dictionary)
TEBBET variant of "tabet", a Scottish word for bodily feeling (W2)
TEBET the 4th month of the Jewish calendar (MWCD10)
TENNET dialectic variant of "tinnet" -- brushwood for making or repairing hedges or fences (OED)
TERRET a ring on a dog"s collar, to which a leash can be attached (OED)
TIBBIT another variant of "tabet" (W2)
TILLIT an early spelling of "tillet" (OED)
TINNIT variant of "tinnet", brushwood (English Dialect Dictionary)
TIPPIT sixteenth and seventeenth-century form of "tippet" (OED)
TIRRIT a fit of fear or temper; an upset of one"s equanimity (OED)
TOOT-TOOT a note or short blast of a horn (OED)
TOTTOT a fruit pigeon from the Pacific island of Guam, named for its cry
TUMUT a town in Australia, on the Murrumbidgee River
TUNG NUT seed of the tung tree. (Encyclopaedia Britannica, 1980)
UBURUBU a town in Nigeria (Encarta World Atlas, Word Ways)
UGOGU a breed of African goats recently used in genetic studies at Liverpool University in England
URAHARU a town in the Kagoshima region, Japan (Encarta World Atlas, Word Ways)
UREMERU a town in Colombia (Encarta World Atlas, Word Ways)
UWOLOWU surpreme god of the Akposo in Togo (Guide to the Gods, Word Ways)
VELLEV a town in Denmark (Times Atlas of the World, Word Ways)
WASSAMASSAW a place name in South Carolina
WOW-WOW the silver gibbon of Java
XITIX a name for L-ascorbic acid (Dictionary of Chemical Names and Symbols, Word Ways)
XOLOX a locality in central Mexico (Official Guide to Railways, Word Ways)
YARAY Puerto Rican fan palms (W3)
YUCUCUY a populated place in Mexico (Official Standard Names Gazetteer, Word Ways)
The Finnish word SAIPPUAKIVIKAUPPIAS (a soapstone seller) is the longest known palindrome in any language according to the Guinness Book of World Records. It is claimed that two other Finnish palindromes are SAIPPUAKUPPINIPPUKAUPPIAS (soap cup trader) and SOLUTOMAATTIMITTAAMOTULOS (the result from a measurement laboratory for tomatoes) although technically the latter is a compound of four words.
In Estonian KUULILENNUTEETUNNELILUUK is the hatch a bullet flies out of when exiting a tunnel.
The Swedish word PORTUGALRALLARLAGUTROP (22 letters) is listed in Guinness, Swedish 1989 edition, but is not found in dictionaries.
According to Maarten van Muijen, the longest palindrome in Dutch is PARTERRESERRETRAP, which is translated "stairs from the main floor to a glass-covered terrace." A reader of this page provided a longer Dutch palindrome, KOORTSMEETSYSTEEMSTROOK, which she translates as "fever measure system strip." Hans Timp says both of these words, and another he provided, NEPPARTERRETRAPPEN, are made for palindroming and are not found in dictionaries. He says the longest real Dutch word which is a palindrome is MEETSYSTEEM, meaning "measuring system."
RELIEFPFEILER is a German word for a relief-decorated column [Charles Turner].
ATT ORDIDROTTA is Swedish meaning to contest with words [Charles Turner].
Miroslav Sedivy writes, “There is one excellent Czech (also Slovak) palindrome unique by its usage: TAHAT (even vertically symmetrical). It means ‘pull’ in sense of pulling a door to open it. So if you see it on a transparent sticker on a glass door (and I've seen many such doors in Czechoslovakia), it's interesting to see people pulling doors from both sides...”
Jan Pulkrábek, a high school teacher of the Czech language, provides these palindromes: NEPOCHOPEN (not understood; the digraph "ch" is considered as one letter in the Czech alphabet), NEPOTOPEN (not submerged), NEZASAZEN (not embedded), and NEZAŘAZEN (not classified).
The Dutch word for kidney is NIER. The French word for kidney is its palindrome, REIN. [Tom De Backer]
EYE is a palindrome in English, Spanish (OJO), and Polish (OKO). [Charles Turner]
Some reversible words are also mirror words, as they become other words in their mirror image, using capital letters. These include OHM/MHO, AIM/MIA, TWAT/TAWT, and TOMTOM/MOTMOT [Yarlagadda Police].
Words which become other words when rotated 180 degrees are WOW/MOM, OHM/WHO, and SWIM/WIMS. Note that OHM appears in both categories [Yarlagadda Police].