[1] : The Collaborative International Dictionary of English v.0.48

head-on \head-on\ 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

[2] : WordNet (r) 2.0

head-on
     adj 1: characterized by direct opposition; "a head-on
            confrontation"
     2: meeting front to front; "a frontal attack"; "a head-on
        collision" syn: frontal
     adv 1: in direct opposition; directly; "we must meet the problem
            head-on"
     2: with the front foremost; "the cars collided head-on"
see also:
frontal 

Head-On >> H Words
Head-On, definition of term: Head-On
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