- crackpot, crank, nut, nut case, nutcase, fruitcake, screwball - a whimsically eccentric person
--1 is a kind of eccentric, eccentric person, flake, oddball, geek
- fruitcake - a rich cake containing dried fruit and nuts and citrus peel and so on
--2 is a kind of cake
--2 has particulars: Christmas cake; simnel