{ Su"mac, Su"mach } (?), n. [F. sumac, formerly sumach (cf. Sp. zumaque), fr. Ar. summāq.] [Written also shumac.] 1. (Bot.) Any plant of the genus Rhus, shrubs or small trees with usually compound leaves and clusters of small flowers. Some of the species are used in tanning, some in dyeing, and some in medicine. One, the Japanese Rhus vernicifera, yields the celebrated Japan varnish, or lacquer.

2. The powdered leaves, peduncles, and young branches of certain species of the sumac plant, used in tanning and dyeing.

{ Su"mac, Su"mach } (?), n. [F. sumac, formerly sumach (cf. Sp. zumaque), fr. Ar. summāq.] [Written also shumac.] 1. (Bot.) Any plant of the genus Rhus, shrubs or small trees with usually compound leaves and clusters of small flowers. Some of the species are used in tanning, some in dyeing, and some in medicine. One, the Japanese Rhus vernicifera, yields the celebrated Japan varnish, or lacquer.

2. The powdered leaves, peduncles, and young branches of certain species of the sumac plant, used in tanning and dyeing.

• Any of various shrubs or small trees of the genus Rhus including the poison ivy and poison oak.
  
• A sour spice popular in the Eastern Mediterranian made from the berries of the plant.