lettuce: any of various plants of the genus Lactuca
herb: a plant lacking a permanent woody stem; many are flowering garden plants or potherbs; some having medicinal properties; some are pests
leflunomide: an anti-TNF compound (trade name Arava) that is given orally; can slow the progression of rheumatoid arthritis by slowing the proliferation of white blood cells which reduces inflammation in the synovium