any of several trees or shrubs of the genus Fortunella bearing small orange-colored edible fruits with thick sweet-flavored skin and sour pulp
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small oval citrus fruit with thin sweet rind and very acid pulp
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kumquat \kum"quat\, n. [Chin. kin keu.] (Bot.) any of several trees or shrubs of the genus {Fortunella} (formerly {Citrus}) of the rue family ({Rutaceae}) (especially {Citrus Japonica}) growing in China and Japan bearing small orange-colored edible fruits with thick sweet-flavored skin and sour pulp; also, any of the small acid, orange-colored citrus fruits of such plants, used mostly for preserves. [Also spelled {cumquat}.] [1913 Webster + WordNet 1.5]
Streets and office corridors are lined with tangerine and kumquat trees, and residents leave grocery stores with ornately wrapped baskets of oranges tucked under their arms.