英语词源字典 - 在线词源网站

headwaters (n.)[headwaters 词源字典]: attested 1530s, then not again until 1792 (in descriptions of Kentucky), so possibly the modern word is a re-formation; see head (n.) "origin of a river" + water (n.1).[headwaters etymology, headwaters origin, 英语词源]
watershed (n.): "line separating waters flowing into different rivers," 1803, from water (n.1) + shed in a topographical sense of "ridge of high ground between two valleys or lower ground, a divide," perhaps from shed (v.) in its extended noun sense of "the part of the hair of the head" (14c.). Perhaps a loan-translation of German Wasser-scheide. Figurative sense is attested from 1878. Meaning "ground of a river system" is from 1878.
waterspout (n.): late 14c., "drainpipe," from water (n.1) + spout (n.). Meaning "whirlwind on open water" is recorded from 1738.