Fraction
late Middle English: via Old French from ecclesiastical Latin fractio(n-) ‘breaking (bread)’, from Latin frangere ‘to break’.
wiktionary
From Middle English fraccioun(“a breaking”), from Anglo-Norman, Old French fraction, from Medieval Latin fractio(“a fragment, portion”), from earlier Latin fractio(“a breaking, a breaking into pieces”), from fractus (English fracture), past participle of frangere(“to break”) (whence English frangible), from Proto-Indo-European *bʰreg- (English break).
etymonline
fraction (n.)
late 14c., originally in the mathematical sense, from Anglo-French fraccioun (Old French fraccion, "a breaking," 12c., Modern French fraction) and directly from Late Latin fractionem (nominative fractio) "a breaking," especially into pieces, in Medieval Latin "a fragment, portion," noun of action from past participle stem of Latin frangere "to break (something) in pieces, shatter, fracture," from Proto-Italic *frang-, from a nasalized variant of PIE root *bhreg- "to break." Meaning "a breaking or dividing" in English is from early 15c.; sense of "broken off piece, fragment," is from c. 1600.
