Meaning

noun any of several Old World shrubby broad-leaved willows having large catkins; some are important sources for tanbark and charcoal

verb cause to become sallow

adjective unhealthy looking

originFrom Middle English salow, salwe, from Old English sealh, from Proto-West Germanic *salh, from Proto-Germanic *salhaz, masculine variant of *salhō, *salhijǭ, from Proto-Indo-European *sh₂lk-, *sh₂lik-. See also Low German Sal, Saal; Swedish sälg; also Welsh helyg, Latin salix (and also a doublet of the thence derived English borrowing salix) probably originally a borrowing from some other…

Etymology from Wiktionary, CC BY-SA 3.0