late 14c., from Old French garniss-, present participle stem of garnir "provide, furnish; fortify, reinforce," from a Germanic stem related to Proto-Germanic *warnejan "be cautious, guard, provide for" (cf. Old High German warnon "to take heed," Old English warnian "to take warning, beware;" see warn). Sense evolution is from "arm oneself" to "fit out" to "embellish," which was the earliest meaning in English, though the others also were used in Middle English. Culinary sense of "to decorate a dish for the table" predominated after c.1700. Older meaning survives in legal sense of "warning of attachment of funds" (1570s). Related: Garnished; garnishing.
late 14c., "set of tableware" (probably a dozen; usually pewter), from garnish (v.). Sense of "embellishments to food" is from 1670s.
overlay with stones (2 Chr. 3:6), adorn (Rev. 21:19), deck with garlands (Matt. 23:29), furnish (12:44). In Job 26:13 (Heb. shiphrah, meaning "brightness"), "By his spirit the heavens are brightness" i.e., are bright, splendid, beautiful.
an embellishment added to a food to enhance its appearance or taste. Simple garnishes such as chopped herbs, decoratively cut lemons, parsley and watercress sprigs, browned breadcrumbs, sieved hardcooked eggs, and broiled tomatoes are appropriate to a wide variety of foods; their purpose is to provide contrast in colour, texture, and taste, and to give a finished appearance to the dish