A thumb thats exceedingly wide and short. Like a chode but its a thumb, hence chumb. See Megan Fox's thumbs for an example!!
A: OMG look at her thumb its so wide and short!! Who has thumbs like that??
B: Oh yeah she's got a chumb!!
B: Oh yeah she's got a chumb!!
by Sickskier1 March 6, 2011
Get the chumbmug. chumbs up!
by Jon Queerbeck February 19, 2012
Get the chumbsmug. by Kaila Mayo April 28, 2008
Get the chumbemug. by Pineapplesjee  April 5, 2019
Get the Blueberry chumb potmug. 