English word fruitcake comes from English fruit, English cake

Detailed word origin of fruitcake

Dictionary entry	Language	Definition
fruit	English (eng)	To produce fruit, seeds, or spores. (as a modifier) Of, pertaining to, or having fruit; (of living things) producing or consuming fruit.. (botany) The seed-bearing part of a plant, often edible, colourful/colorful and fragrant, produced from a floral ovary after fertilization.. (dated, colloquial, derogatory) A homosexual or effeminate man.. An end result, effect, or consequence; [...]
cake	English (eng)	(transitive) Coat (something) with a crust of solid material.. To form into a cake, or mass. (slang) A trivially easy task or responsibility; from a piece of cake.. (slang) Money.. A block of any of various dense materials.. A rich, sweet dessert food, typically made of flour, sugar, and eggs and baked in an oven, and often covered in icing.. A small mass of baked dough, especially a thin [...]
fruitcake	English (eng)	(US, slang, colloquial, derogatory, dated) A male homosexual.. (chiefly, US, and, Canada, colloquial, derogatory) A crazy or eccentric person.. A cake containing dried fruits and, optionally, nuts, citrus peel and spice.