Kitten
late Middle English kitoun, ketoun, from an Anglo-Norman French variant of Old French chitoun, diminutive of chat ‘cat’.
wiktionary
From Middle English kitoun, kytton, kyton, keton(“kitten”). Seemingly from, and usually explained as being from, unattestedAnglo-Norman *kitoun, *ketun (compare Old French chitoun, cheton, chaton(“kitten”), diminutive of cat, chat(“cat”)); whence Modern French chaton(“kitten”). Similar words of Germanic origin may have reinforced this word; compare English kitling(“kit, kitten”), Low German Kitten(“kitten”), Icelandic kettlingur(“kitten”), Middle English chitte("whelp, pup", see chit).
The idea that kitoun, rather than being of Anglo-Norman origin, was in fact a purely Germanic derivation from one of these words is etymologically problematic, but cannot be definitively ruled out.
etymonline
kitten (n.)
late 14c., kitoun, "the young of a domesticated cat," probably from an Anglo-French variant of Old French chaton, chitoun (Old North French caton) "little cat," a diminutive of chat "cat," from Late Latin cattus (see cat (n.)). In playful use, "a young girl, a sweetheart," from 1870. As a verb, "bring forth kittens," late 15c. To have kittens "lose one's composure" is from 1908.
