Knife
late Old English cnīf, from Old Norse knífr, of Germanic origin.
wiktionary
From Middle English knyf, knif, from late Old English cnīf, from Old Norse knífr (compare Danish/Swedish/Norwegian kniv), North Frisian Knif from Proto-Germanic *knībaz (compare Low German Knief, Luxembourgish Knäip(“penknife”)), from *knīpaną(“to pinch”) (compare Dutch knijpen, Low German kniepen, Old High German gniffen), from Proto-Indo-European *gneybʰ- (compare Lithuanian gnýbti, žnýbti(“to pinch”), gnaibis(“pinching”)). Replaced Middle English sax(“knife”) from Old English seax(“knife, dagger”), and replaced Middle English coutel, qwetyll(“knife”) from Old French coutel(“knife”).
The verb knife is attested since the mid 1800s; [1] the variant knive is attested since 1733.
etymonline
knife (n.)
"hand-held cutting instrument consisting of a short blade and handle," late Old English cnif, probably from Old Norse knifr "knife, dirk," from Proto-Germanic *knibaz (source also of Middle Low German knif, Middle Dutch cnijf, German kneif), a word of uncertain origin. To further confuse the etymology, there also are forms in -p-, such as Dutch knijp, German kneip. French canif "penknife" (mid-15c.) is probably of Germanic origin, perhaps from Frankish. For pronunciation, see kn-.
knife (v.)
1865, "stab or kill with a knife," from knife (n.). Intransitive meaning "move as a knife does" is from 1920. Related: Knifed; knifing.
