[kok-shoor, -shur]


perfectly sure or certain; completely confident in one's own mind: She was cocksure that she was able to do the job better than anyone else.
too certain; overconfident: He was so cocksure he would win the election that he didn't even bother to campaign.
Obsolete. perfectly secure or safe.

Origin of cocksure

First recorded in 1510–20; cock1 + sure
Related formscock·sure·ly, adverbcock·sure·ness, noun

Synonyms for cocksure Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for cocksure

Contemporary Examples of cocksure

Historical Examples of cocksure

  • It would have done my heart good for the rest of my life if I could have got away then and fooled that Hun, he was so cocksure.

  • It had slowly dawned upon Fred that he was listening to an appeal for mercy, a cry for help from this jaunty, cocksure brother.

    Otherwise Phyllis

    Meredith Nicholson

  • This fiance of mine that you seem so cocksure about has no existence.

    When Ghost Meets Ghost

    William Frend De Morgan

  • Yet Big Tom was plainly not so cocksure of himself as he had been, while the scoutmaster wore an air of complete confidence.

  • I fear I grow too cocksure of my literary attainments out here, with none to check me.

    An Ocean Tramp

    William McFee

British Dictionary definitions for cocksure



overconfident; arrogant
Derived Formscocksurely, adverbcocksureness, noun

Word Origin for cocksure

C16: of uncertain origin
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 cocksure

1520s, "certain," from cock (n.1) + sure (adj.). Probably "as assured as a cock." "The word was originally perfectly dignified, and habitually used in the most solemn connexions" [OED].

Online Etymology Dictionary, © 2010 Douglas Harper