- don't know: Who did it? I dunno!
Origin of dunno
First recorded in 1835–45
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for dunno
I dunno as wimmin horse doctors is very common, but I dunno why not.
I get a horse with somethin' the matter of his foot, and I dunno what.
I dunno how you're goin' to git along with men-folks, if ye offer 'em the whip-hand.Tiverton Tales
"Why, I dunno's there's anything in the way of it," she said, soberly.
I've studied a good deal over her, an' I dunno's I've quite got to the bottom of her yit.
- (I) do not know
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
Word Origin and History for dunno
colloquial for "(I) don't know," first attested 1842 in American English.
Online Etymology Dictionary, © 2010 Douglas Harper