gall: Gall ‘bile’ [12], and by metaphorical extension ‘bitterness’ and ‘effrontery’, was borrowed from Old Norse gall. It gets its name ultimately from its colour, for its prehistoric Germanic ancestor *gallam or *gallon (which also produced German galle and Dutch gal) goes back to Indo-European *ghol-, *ghel-, which also gave English gold, jaundice, yellow, and yolk.
The relationship of the two other English words gall (‘skin sore’ [14], whence the verbal use ‘exasperate’, and ‘plant swelling’ [14]) to gall ‘bile’ and to each other is not clear. The immediate source of ‘skin sore’ was Middle Low German galle ‘sore’, but ‘bile’ could easily have led via ‘astringent substance’ to ‘sore place’, and it may be that ultimately the Middle Low German word is connected with gall ‘bile’. Gall ‘plant swelling’ has been traced back via Old French galle to Latin galla ‘plant gall’, but some later descendants of this were used for ‘swelling on an animal’s leg’, further adding to the confusion. => gold, jaundice, yellow, yolk
gall (n.1)
"bile, liver secretion," Old English galla (Anglian), gealla (West Saxon) "gall, bile," from Proto-Germanic *gallon "bile" (cognates: Old Norse gall "gall, bile; sour drink," Old Saxon galle, Old High German galla, German Galle), from PIE root *ghel- (2) "to shine," with derivatives referring to bright materials and gold, and bile or gall (see glass). Informal sense of "impudence, boldness" first recorded American English 1882; but meaning "embittered spirit, rancor" is from c. 1200, from the medieval theory of humors.
gall (n.2)
"sore on skin caused by rubbing or chafing," Old English gealla "painful swelling, sore spot on a horse," probably from Latin galla "gall, lump on plant," originally "oak-gall" (see gall (n.3)). Perhaps from or influenced by gall (n.1) on notion of "poison-sore." Meaning "bare spot in a field" (1570s) is probably the same word. German galle, Dutch gal also are said to be from Latin.
gall (v.)
"to make sore by chafing," mid-15c., from gall (n.2). Earlier "to have sores, be sore" (early 14c.). Figurative sense of "harass, vex, irritate, chafe the spirit of," is from 1570s. A past-participle adjective gealled is found in Old English, but OED says this is from the noun. Related: Galled; galling.
gall (n.3)
"excrescence on a plant caused by the deposit of insect eggs," especially on an oak leaf, late 14c., from Latin galla "oak-gall," which is of uncertain origin. They were harvested for use in medicines, inks, dyes.