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definitions

dumb-ass

or dumb·ass

[duhm-as]
noun Slang: Vulgar.
  1. a thoroughly stupid person; blockhead.

Origin of dumb-ass

1970–75; Americanism
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for dumb-asses

dumb-ass

noun
  1. a stupid person
adjective
  1. extremely stupid
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012