Webster's Revised Unabridged Dictionary · 1913

Headstrong

Headstrong (-strong`; 115) , adjective

1.
Not easily restrained; ungovernable; obstinate; stubborn.
Now let the headstrong boy my will control. — Dryden
2.
Directed by ungovernable will, or proceeding from obstinacy; as, a headstrong course. — Dryden