etymologeek.com dictionary
English word but comes from Old French bouter, Old English būtan, Old English butan (Except for, but, unless Without, except.), Proto-Indo-European *bʰawd-.

But etymology history

But detailed word origin explanation

Dictionary entryLanguageDefinition
bouter Old French (fro) (reflexive, se bouter) to enter (into). To place; to put. To strike; to hit.
būtan Old English (ang)
butan Old English (ang) Except for, but, unless Without, except.
*bʰawd- Proto-Indo-European (ine-pro)
*bʰudnó- Proto-Indo-European (ine-pro)
*buttaz Proto-Germanic (gem-pro) End; piece Cut off; chopped off; stumpy.
*butt Old English (ang)
byt Old English (ang)
bytt Old English (ang)
botte Middle English (enm)
but English (eng) (obsolete, outside, Scotland) Outside of.. Without, apart from, except. (Australian, conjunctive) Though, however.. Merely, only.. Used as an intensifier. (archaic) Without its also being the case that; unless that (introducing a necessary concomitant).. (obsolete) Except with; unless with; without.. (obsolete) Only; solely; merely.. (obsolete) until. Except (for), excluding. Often preceded [...]

Words with the same origin as but

Descendants of bouter
button
Descendants of būtan
about and baht bout butt for halibut nor whereabouts
Descendants of *bʰawd-
bit boot booty bra bro brother bruv bub bubba bud buddy butter debut