lavender
n.
"fragrant plant of the mint family," c.1300, from Anglo-French lavendre, Old French lavendre, from Medieval Latin lavendula "lavender" (10c.), perhaps from Latin lividus "bluish, livid." Associated with French lavande, Italian lavanda "a washing" (from Latin lavare "to wash;" see lave) because it was used to scent washed fabrics and as a bath perfume. (An identical Middle English word meant "laundress, washerwoman;" also, apparently, "prostitute, whore; camp follower" and is attested as a surname from early 13c.). The adjective meaning "pale purple color" is from 1840.