'Ohh yes winter is here and the girls are out and about. There's Gorilla's thumbs all over the place'
by Mongymax October 26, 2007
A penis - particularly a penis that is curious and/or searching for something. The gorilla thumb might be particularly hairy or thick, although not necessarily. Ideally, it doesn't have a fingernail.
by bullfrogboy October 09, 2008
by JimboSlice13 July 14, 2017