名詞 obverse:

1. the more conspicuous of two alternatives or cases or sides
2. the side of a coin or medal bearing the principal stamp or design

1. Inference of the obverse of a proposition.
   換質(zhì)法推導(dǎo)一個(gè)命題的方法
2. The obverse of love is hate.
   與愛相對(duì)的是恨。
3. The head of the Queen appears on the obverse of British coins.
   英國(guó)硬幣的正面有女王的頭像。

ob.verse

adj.Abbr. obv.（形容詞）縮寫 obv.
Facing or turned toward the observer:
正面的：面對(duì)或轉(zhuǎn)向觀察者的：
例句：
the obverse side of a statue.
塑像的正面

Serving as a counterpart or complement.
對(duì)應(yīng)面的：作為副本或補(bǔ)充物的
n.（名詞）

The side of a coin, medal, or badge that bears the principal stamp or design.
正面：幣、獎(jiǎng)?wù)禄蛐錁?biāo)的一面，帶有主要的戳或圖案
The more conspicuous of two possible alternatives, cases, or sides:
較明顯的一面：兩個(gè)可能的互換物、方案或方面中更引人注目的那個(gè)：
例句：
the obverse of this issue.
這個(gè)問題中更引人注目的一面

Logic The counterpart of a proposition obtained by exchanging the affirmative for the negative quality of the whole proposition and then negating the predicate:
【邏輯學(xué)】 換質(zhì)命題：換質(zhì)說明法，反換命題的配對(duì)命題，將命題假設(shè)中的所有肯定換成否定，再把結(jié)論變?yōu)榉穸ǘ玫降拿}：
例句：
The obverse of .Every act is predictable. is .No act is unpredictable..
.Every act is predictable.的反換命題說法是.No act is unprecictable.

來源：
Latin obversus [past participle of] obvertere [to turn toward] * see obvert
拉丁語(yǔ) obversus [] obvertere的過去分詞 [向…轉(zhuǎn)身，轉(zhuǎn)向] *參見 obvert

【引伸】
obverse.ly
adv.（副詞）