This natural oil comes from a fruit, Citrus bergamia, a bitter relative of the orange, lemon and lime.

这种天然的香精来源一种和桔子，柠檬有亲缘性的水果，叫香柠檬橘（Citrus bergamia）。

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A small tree(Citrus aurantium subsp. bergamia) commercially grown chiefly in southern Italy for its sour citrus fruits, the rinds of which yield an aromatic oil.

佛手柑，香柠檬一种小树（酸橙亚种贝加毛橙），主要在意大利南部进行商业性种植。

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Citrus bergamia, as it's known in botanical circles, first showed up 300 years ago in Southern Italy, the result of crossbreeding a sour orange with "something else, " variously identified as a citron, a lemon, a lime or a Palestine sweet lime.

WSJ: Bergamot Is No Lemon