I. äb-ˈvərs, əb-, ˈäb-ˌ adjective
Etymology: Latin obversus, from past participle of obvertere to turn toward, from ob- toward + vertere to turn — more at ob- , worth
Date: circa 1656
1. : facing the observer or opponent
2. : having the base narrower than the top
an obverse leaf
3. : constituting the obverse of something : opposite
• ob·verse·ly adverb
II. ˈäb-ˌvərs, äb-ˈ, əb-ˈ noun
Date: 1658
1. : the side of a coin or currency note bearing the chief device and lettering ; broadly : a front or principal surface
2. : a counterpart having the opposite orientation or force
their rise was merely the obverse of the Empire's fall — A. J. Toynbee
also : opposite 1
joy and its obverse , sorrow
3. : a proposition inferred immediately from another by denying the opposite of what the given proposition affirms
the obverse of “all A is B ” is “no A is not B”