tigernut, nearly cosmopolitan perennial ( Cyperus esculentum ) of the family Cyperaceae (sedge family) of the same genus as the papyrus plant. The tigernut has been cultivated since early times (chiefly in S Europe and W Africa) for its small, tuberous rhizomes, which are eaten raw or roasted, used for hog feed, and pressed for the juice to make a beverage. A nondrying oil (usually called chufa) is also obtained from the rhizome. In W Africa the plant often grows in great concentration and is gathered from the wild. In the S United States it is sometimes a troublesome weed in planted fields. Other names are earth almond and yellow nut grass. The tigernut is classified in the division Magnoliophyta, class Liliopsida, order Cyperales, family Cyperaceae.