Webster’s Revised Unabridged Dictionary · 1913
Obverse
Ob·verse′ (ŏb·vẽrs′), a. [L. obversus, p. p. of obvertere. See Obvert.] Having the base, or end next the attachment, narrower than the top, as a leaf.
Ob′verse (ŏb′vẽrs), n. [Cf.F. obverse, obvers. See Obverse, a.] 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.