ob·verse /ɑbˈvɝs, əb, ˈɑbˌ/
  表面,正面,反面(a.)尖端闊大的,正面的,對應面的
  Ob·verse a.  Having the base, or end next the attachment, narrower than the top, as a leaf.
  Ob·verse n.
  1. The face of a coin which has the principal image or inscription upon it; -- the other side being the reverse.
  2. Anything necessarily involved in, or answering to, another; the more apparent or conspicuous of two possible sides, or of two corresponding things.
     The fact that it [a belief] invariably exists being the obverse of the fact that there is no alternative belief.   --H. Spencer.
  ◄ ►
  obverse
       n 1: the more conspicuous of two alternatives or cases or sides;
            "the obverse of this issue"
       2: the side of a coin or medal bearing the principal stamp or
          design [ant: reverse]