adj. 1. characterized by direct opposition; as, a head-on confrontation. Syn. -- head-to-head. [ WordNet 1.5 ]
2. Without evasion or compromise; as, his usual head-on fashion; to meet a problem head-on. Syn. -- downright, flat-footed, forthright, foursquare, straightforward. [ WordNet 1.5 ]
3. Meeting front to front; used mostly of collisions between vehicles; as, a head-on automobile collision. Syn. -- frontal. [ WordNet 1.5 ]