From The Food Encyclopedia by Jacques Rolland and Carol Sherman
Similar to a miniature orange, but not a citrus fruit, of the genus Fortunella, orange and oval, the size of an olive. Kumquats are sour tasting, but are edible including the rind. The shrubby kumquat tree is native to China and is valued there because it is resistant to cold and grows farther north than any other citrus-like tree. Also grown in Japan and the U.S. The name comes from the Cantonese chin kan, meaning "golden mandarin." Probably because of its funny name, W.C. Fields used it in one of his most infamous lines: "How about a kumquat, my little chickadee?" See also calamondin.
