Fuck in a word
This is surprising because Chaucer had about a dozen different spellings of the word 'cunt'. The document in question also contains liberal use of the term 'windfucker' and 'fuckbeggar' which I will be incorporating into my lexicon with all haste.
> A great discovery has been made by Dr Paul Booth, a fellow of Keele University. It is a 14th-century example of fuck. We might think the word Anglo-Saxon, but it’s hard to find written examples before the 16th century. Chaucer never uses it. The earliest citation in the Oxford English Dictionary is in a poem from 1500 in the surprising form gxddbov. That is a cipher which, by shifting each letter back a place in the alphabet, reveals fuccant, a dog-Latin third person plural of the verb.