Headstrong
Pronunciation : Head"strong`
Part of Speech : a.
Definition : 1. Not easily restrained; ungovernable; obstinate; stubborn. Not let headstrong boy my will control. Dryden.
2. Directed by ungovernable will, or proceeding from obstinacy. Dryden.
Syn. -- Violent; obstinate; ungovernable; unratable; stubborn; unruly; venturesome; heady.
Source : Webster's Unabridged Dictionary, 1913