baseyoudaoicibaDictYouDict[base 词源字典]
base: There are two distinct words base in English. Base meaning ‘lower part, foundation’ [14] came either via Old French base or was a direct anglicization of Latin basis (acquired by English in its unaltered form at around the same time). The Latin word in its turn came from Greek básis, which meant originally ‘step’ and came ultimately from the Indo-European base *gwm-, from which English gets come; the semantic progression involved was ‘going, stepping’ to ‘that on which one walks or stands’ to ‘pedestal’.

The derivative basement [18] is Italian in origin (Italian basamento means ‘base of a column’), but probably reached English via early modern Dutch basement ‘foundation’. Base meaning ‘low’ [14] comes via Old French bas from medieval Latin bassus ‘short, low’. The ultimate antecedents of this are uncertain, although some have suggested a connection with básson, the comparative form of Greek bathús ‘deep’.

The adjective bass is historically the same word as base, but since the 16th century has been distinguished from it by spelling.
=> basis; bass[base etymology, base origin, 英语词源]
base (n.)youdaoicibaDictYouDict
"bottom, foundation, pedestal," early 14c., from Old French bas "depth" (12c.), from Latin basis "foundation," from Greek basis "step, pedestal," from bainein "to step" (see come). The military sense is from 1860. The chemical sense (1810) was introduced in French 1754 by French chemist Guillaume-François Rouelle (1703-1770). Sporting sense of "starting point" ia from 1690s, also "destination of a runner" (1812). As a "safe" spot in a tag-like game, suggested from mid-15c. (as the name of the game later called prisoner's base).
base (adj.)youdaoicibaDictYouDict
late 14c., "low, of little height," from Old French bas "low, lowly, mean," from Late Latin bassus "thick, stumpy, low" (used only as a cognomen in classical Latin, humilis being there the usual word for "low in stature or position"), possibly from Oscan, or Celtic, or related to Greek basson, comparative of bathys "deep." Figurative sense of "low in the moral scale" is first attested 1530s in English, earlier "servile" (1520s). Base metals (c. 1600) were worthless in contrast to noble or precious metals.
base (v.)youdaoicibaDictYouDict
"to place on a foundation," 1841, from base (n.). Related: Based; basing.