lime is a citrus fruit, which is typically round, green in color, 3–6 centimeters (1.2–2.4 in) in diameter, and contains acidic juice vesicles.
There are several species of citrus trees whose fruits are called limes, including the Key lime (Citrus aurantiifolia), Persian lime, kaffir lime, and desert lime. Limes are a rich source of vitamin C, are sour, and are often used to accent the flavors of foods and beverages. This small green citrus fruit providing juice or peel that is added to food dishes for a refreshing, tart flavor. It is the smallest of the citrus fruit family. The flavor of a lime is stronger and more tart than a lemon, but in most cases they are interchangeable in recipes.