ANTICONSTITUTIONNELLEMENT (25 letters, unconstitutionally) is a long word.
BELLE-FAMILLE is the longest word consisting only of letters in the first half of the alphabet. PROTOTYPONS is the longest word consisting only of letters in the second half of the alphabet.
The longest words with no letter repeating are: CRYPTOGAMIQUES, STYLOGRAPHIQUE, XYLOGRAPHIQUES.
The longest word with no consonant repeating is PNEUMATICOHYDRAULIQUES. The longest with no vowel repeating is PSYCHOSTIMULANTES.
The shortest words containing all the vowels are: AUTONYMIE, BOYAUDIER, BOYAUTIEZ, GUERROYAI, JOUAIENT, (imperfect form of "jouer", "to play" in the third person, plural), NOYAUTIEZ, PAUMOYIEZ, ROUGEOYAI, ROYAUMIEZ, SEYMOURIA.
Longest words with one vowel are BORCHTCHS and SCHPROMMS. Shorter words are: BORTSCHS, PSCHENTS, SCHLAMMS, SCHLICHS, SCHNICKS, SCHNOCKS, SCRATCHS, STRETCHS.
The longest words containing only one vowel, if allowed to repeat are REENSEMENCEMENTS, ENTREPENETRERENT, DEREGLEMENTERENT.
CONTREPLAQUAMES contains the letters LMNOPQRSTU.
The longest words with alternating vowels and consonants are ADIPOSOGENITALES and ALUMINOSILICATES.
SEMNOPITHEQUE and M'AS-TU-VU contain the alphabetical sequences MNOP and STUV. HAUTS-RELIEFS contains the UTSR reverse-alphabetical sequence.
Three dotted letters in a row are found in Nijinski, Yangzijiang, Shijiazhuang.
Long anagrams are INTERDEPARTEMENTALES/DEPARTEMENTALISERENT and INTERTROPICALES/TROPICALISERENT.
The most frequently occurring letters are E,S,A,N,T,I,R,U,L,O.
EEE is found in AGREEE, ANUCLEEE, BEEE, CAPEEE, CONGREEE, CREEE, DEGREEE, DELINEEE, ENUCLEEE, GREEE, GUEEE, INCREEE, MAUGREEE, MONONUCLEEE, NUCLEEE, PLURINUCLEEE, PROCREEE, RAGREEE, RECREEE, REEE, REGREEE, SUPPLEEE, TOREEE.
III is found in GOIIIM.
The longest words consisting only of letters used in hexadecimal numerals are FACE-A-FACE, ABCEDEE, ACCEDEE, CACABEE, DECEDEE, EFFACEE, FABACEE.
The longest words consisting only of short letters are concurrençasses, concurrencerons, réensemençasses, réensemencerons, ressourçons-nous. The longest word consisting only of long letters is fifty-fifty.
The longest words with a horizontal line of symmetry are COCCIDIE and DECOCHEE. The longest words consisting only of letters with a vertical line of symmetry are TUYAUTAIT and VOUVOYAIT.
CIVIL and MILLI are the longest words consisting only of letters used in Roman numerals.
CONSTITUTIONNALISASSIONS is the longest word that does not contain E.
APERIODIQUE is the longest word containing the vowels in alphabetical order.
EAU is made entirely of vowels, with its pronunciation making a fourth vowel "O."
AUTOMATISEERAIENT is the longest word which contains the five vowels in reverse alphabetical order. Other such words are RUDOIERA and TUTOIERA.
CASCARAS-SAGRADAS is the longest word containing A as the only vowel. DEREGLEMENTERENT and REENSEMENCEMENTS are the longest words containing E as the only vowel. The longest word containing I as the only vowel are DISTINCTIFS, INDISTINCTS, INSTINCTIFS, MISSISSIPPI, SCRIPTGIRLS. The longest word with O as the only vowel is PHOTOCOMPOSONS. The longest word with U as the only vowel are CUCURUZZU, JULLUNDUR, LUSTUCRUS, TURLUTUTU. The longest word with Y as the only vowel is FLYSCHS.
The shortest French pangram is: "portez ce vieux whisky au juge blond qui fume."
The longest word with its letters in alphabetical order is AEGILOPS. Shorter words with this property are: ACCENT, ACCORT, AFFINS, AFFLUX, BELLOT, BIJOUX, BILLOT, CHINTZ, DEHORS, EFFORT. The longest words with their letters in reverse alphabetical order are SNIFFEE, SPOLIEE, VOLIGEA, VOLIGEE.
The longest word with every letter occuring twice is CONCENTRATIONNAIRE. The longest word with every letter occurring at least twice is TRANSISTORISASSIONS.
COMMISSIONNEE has four sets of double letters.
Longest palindromes are ESSAYASSE, MALAYALAM, and RESSASSER.
The longest reversible words are SLOVENES/SENEVOLS, REGAGNER/RENGAGER, ESSAYAGE/EGAYASSE, REGNASSE/ESSANGER, SECRETER/RETERCES.
The longest words with Rot13 are PERCHER/CREPURE, RAGREER/ENTERRE, RAVIERE/ENIVRER.
CHERCHER, like HOTSHOTS is repeating, but with asymmetrical pronunciation [CH like SH in SHOW, first ER like AIR, second ER like AY in DAY (RP)].
ENDOLORI/INDOLORE: only one letter to move from one to the other, yet they are virtual antonyms (sore/painless).
The feminine first names IRENE and ELISE are made masculine by adding an E, the reverse of the usual rule of French grammar.
OISEAU exhibits the 'fish-ghoti' phenomenon: it is pronounced 'WAZO' (long O)
BENI-OUI-OUI (yes-man) contains 7 consecutive vowels.
SCHTROUMPFS (name for cartoon characters, English SMURFS) is monosyllabic
M'AS-TU-VU (show-off) is made of 4 parts, with only 7 letters
prim'Holstein (a variety of cow) contains a capital letter inside a word
The most usual spelling of the Jewish holy day is 'HANOUKKA, and to my knowledge is the only French word that doesn't begin with a letter
NIEME exhibits the same phenomenon as its English counterpart NTH : it is pronounced beginning with a nonexistent letter (approximately AYNYEM)
Nnumbers beginning with 'CENT' or 'MILLE' (hundred and thousand) don't need to be split (CENT UN rather than CENT ET UN, although this mistake is quite frequent nowadays), but 101 and 1001 are read CENT ET UN and MILLE ET UN when meaning 'umpteen'.
Among words with different pronounciations according to meaning, a spectacular item is COUVENT, which is monosyllabic as a verb form ([they] hatch) and disyllabic as a noun (convent). 'LES POULES DU COUVENT COUVENT' (the convent's hens are hatching) is a classical tongue-twister for foreigners.
CAMPHRE (camphor) and CHANVRE (hemp) don't rhyme with anything ... but they do with each other in Alsace, where the German accent is frequent.
OURS is pronounced using three phonemes (OO-R-S) in the singular, and two (OO-R) in the plural (well, not nowadays); note that the English word OURS is used in French (pronounced OORS) for the list of contributors to a newspaper (they're ours).
The following table shows words with the most occurrences of each letter.
| a | cascara-sagrada, Santa Reparata Di Balagna |
| b | baobab |
| c | cache-cache |
| d | addenda, Saint-Médard-d'Excideuil |
| e | réensemencee, Sainte-Eugenie-de-Villeneuve |
| f | fifty-fifty, Pfaffenhoffen |
| g | gigogne, Saint-Georges-de-Grehaigne |
| h | hachich, Hochhuth |
| i | indivisibilité |
| j | jojo |
| k | knickerbockers |
| l | lamellé-collé, Llullaillaco Villers-le-Tilleul |
| m | mammectomie |
| n | non-interventionniste |
| o | odontostomatologie |
| p | présupposition, appropria, pupipare, Petit-Fort-Philippe |
| q | quelque, aquatique, quoique, quadratique |
| r | arrière-grand-mère, Chartrier-Ferrière, referrer |
| s | assassinassions, ressassasses |
| t | trottinette, Velotte-et-Tatignecourt |
| u | turlututu, Poursiugues-Boucoué |
| v | servovalve, Villeneuve-Saint-Vistreville |
| w | bow-window |
| x | luxueux, lexicaux, axiaux |
| y | hydroxyethylcellulose |
| z | zozotez |
In addition, MWCD10 says these words are often used interjectionally: adieu, au revoir ball, bam, bang, bon voyage, bosh, bother, botheration, boy, brava, bravo, come on, f***, fudge, go to, good-by, goodness, hard cheese, hard lines, hello, here, huzza, indeed, Jove, know, like, man, mean, my, nerts, no sweat, peace, period, rather, right on, rot, shuck, silence, skoal, so, son of a b****, son of a gun, there, timber, truly, whatever, whew, whisht, whist, whoop, whoosh.
MWCD11, published in 2003, added the interjection OY, which it dated to 1892.
The Oxford Dictionary of English, published in 2003, added the interjection BADA BING (also "bada bing bada boom") as an exclamation to emphasize that something will happen effortlessly and predictably.
The OED2 lists 168 interjections, some with alternate spellings. The interjections with the most recent first citations are YEUCH (1979), YUCK (1966), KAY (1959), and ROG (1955) [Philip Bennett].