lush (adj.)
mid-15c., "lax, flaccid, soft, tender," from Old French lasche "soft, succulent," from laschier "loosen," from Late Latin laxicare "become shaky," related to Latin laxare "loosen," from laxus "loose" (see lax). Sense of "luxuriant in growth" is first attested c.1600, in Shakespeare. Applied to colors since 1744. Related: Lushly; lushness.
lush (n.)
"drunkard," 1890, from earlier (1790) slang meaning "liquor" (especially in phrase lush ken "alehouse"); perhaps a humorous use of lush (adj.) or from Romany or Shelta (tinkers' jargon).
LUSHEY. Drunk. The rolling kiddeys had a spree, and got bloody lushey; the dashing lads went on a party of pleasure, and got very drunk. ["Dictionary of Buckish Slang, University Wit, and Pickpocket Eloquence," London, 1811]