depends on which dictionary you want to use...
English
zymurgy (the art or science of fermentation) -- Shorter Oxford English Dictionary, Macquarie Encyclopedic Dictionary [D Tse], Webster's Dictionary (1991 edition) [Maarten van Beek]

also: Zyrian (former term for the language Komi) -- New Oxford Dictionary of English, 2001

also: zyxomma (type of dragonfly) -- Collins New English Dictionary 1956 edition

also: zyxt (obsolete Kentish dialect form, 2nd person singular indicative present of See v.) -- Oxford English Dictionary

also: zyzonym (once seen, source forgotten -- can anyone help?)

also: zyzzyva (tropical American weevil) -- American Heritage Dictionary [Muke Tever] (But this looks to my cynical eye like someone has made up the name with the intention of it being the last word in the dictionary. Hmm.); the American Heritage Electronic Dictionary has the genitive plural form: zyzzyvas' [Jeffrey Henning]

also (but surely this is just cheating): zzz (colloq.: a sleep -- from the convention used, esp. by cartoonists, to represent sleep or the sound of snoring) -- Macquarie Australian Dictionary [Tristan McLeay]

Old English: yðworigende (wandering on the waves, wave-wandering (fish)) - A Concise Anglo-Saxon Dictionary by JR Clark Hall [Andrew Smith]
Herees the entire site:
Last Word


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