fix: [15] Fix comes ultimately from Latin fīgere ‘fasten’. Its past participle fīxus made its way into English along two distinct routes, partly via the Old French adjective fix ‘fixed’, and partly via the medieval Latin verb fīxāre. Derived forms in English include affix [15], prefix [17], suffix [18], and transfix [16], and also fichu ‘scarf’ [19]: this came from the past participle of French ficher ‘attach’, which is descended from Vulgar Latin *figicāre, another derivative of figere. => affix, prefix, suffix, transfix
fix (v.)
late 14c., "set (one's eyes or mind) on something" (a figurative use), probably from Old French verb *fixer, from fixe "fixed," from Latin fixus "fixed, fast, immovable; established, settled," past participle adjective from figere "to fix, fasten, drive, thrust in; pierce through, transfix," also figurative, from PIE root *dhigw- "to stick, to fix" (see dike).
Sense of "fasten, attach" is c. 1400; that of "to make (colors, etc.) fast or permanent" is from 1660s. The meaning "settle, assign" evolved into "adjust, arrange" (1660s), then "repair" (1737). Sense of "tamper with" (a fight, a jury, etc.) is from 1790. As euphemism for "castrate a pet" it dates from 1930. Related: Fixed; fixing.
fix (n.)
"position from which it is difficult to move," 1809, American English, from fix (v.). Meaning "dose of narcotic" is from 1934, shortened from fix-up (1867, originally in reference to liquor). Meaning "reliable indication of the position of a ship, plane, etc." (by reference to fixed positions) is from 1902.