Cocksure

a.	1.	Perfectly safe. We steal as in a castle, cocksure: . . . we walk invisible. - Shak.
	2.	Quite certain. I thought myself cocksure of the horse which he readily promised me. - Pope.
	3.	overconfident; - of people; as, the team was so cocksure of winning that they didn't practice in the week before the big game..

Adj.

1.

cocksure - marked by excessive confidence; "an arrogant and cocksure materialist"; "so overconfident and impudent as to speak to the queen"; "the less he knows the more positive he gets" Synonyms: overconfident, positive

arrogant, assured, certain, confident, convinced, decided, determined, hubristic, overconfident, oversure, overweening, persuaded, poised, pompous, positive, proud, reassured, secure, self-assured, self-confident, self-important, self-reliant, sure, unafraid, undoubting, unfaltering, unhesitating, unwavering