cake vs fruitcake

cake and fruitcake both are nouns.

Word	Noun	Adjective	Verb	Adverb
cake	Yes	No	Yes	No
fruitcake	Yes	No	No	No

As nouns, fruitcake is a hyponym of cake; that is, fruitcake is a word with a more specific, narrower meaning than cake:

cake: baked goods made from or based on a mixture of flour, sugar, eggs, and fat
fruitcake: a rich cake containing dried fruit and nuts and citrus peel and so on

cake (noun)	fruitcake (noun)
a block of solid substance (such as soap or wax)	a rich cake containing dried fruit and nuts and citrus peel and so on
baked goods made from or based on a mixture of flour, sugar, eggs, and fat	a whimsically eccentric person
small flat mass of chopped or ground food

cake (verb)	fruitcake (verb)
form a coat over