grape·fruit (gr?p?fro?ot?)n.1. A tropical or semitropical evergreen tree (Citrus paradisi) cultivated for its edible fruit.2. The large, round fruit of this tree, having a yellow rind and juicy, somewhat acid pulp.[Probably so called because the fruit grows in clusters.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.grapefruit (??re?p?fru?t) n, pl -fruit or -fruits1. (Plants) a tropical or subtropical cultivated evergreen rutaceous tree, Citrus paradisi2. (Plants) the large round edible fruit of this tree, which has yellow rind and juicy slightly bitter pulpCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014grape?fruit (?gre?p?frut) n. 1. a large, roundish, yellow-skinned, edible citrus fruit having a juicy, acid pulp. 2. the tropical or semitropical tree, Citrus paradisi, yielding this fruit. [1805?15; appar. from the resemblance of its clusters to those of grapes] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.