what is grapefruit
Full Definition of GRAPEFRUIT. 1. plural grapefruit or grapefruits: a large citrus fruit with a bitter yellow rind and inner skin and a highly flavored somewhat acid juicy pulp.2. : a small roundheaded tree (Citrus paradisi) of the rue family that produces grapefruit.See grapefruit defined for English-language learners.ull Definition of GRAPEFRUIT. 1. plural grapefruit or grapefruits: a large citrus fruit with a bitter yellow rind and inner skin and a highly flavored somewhat acid juicy pulp. 2.