variation

cの前: oc-

fの前: of-

pの前: op-

1. denoting exposure or openness: obverse

露出・開放性を表す

expressing meeting or facing: observe

会議や立会を表現する

2. denoting opposition, hostility, or resistance: obstacle

反対・敵意・抵抗を表す

denoting hindrance, blocking, or concealment: obviate | obliterate

妨害・遮断・隠蔽を表す

3. denoting extensiveness, finality, or completeness: obsolete | obdurate

広大さ、最終的であること、完全であることを表す

4. (in modern technical words) inversely; in a direction or manner contrary to the usual: obconical

(現代の技術的な用語で)逆の; 方向・方法が普通とは対局にある;

from Latin ob ‘towards, against, in the way of’.

Ob- occurs mainly in words of Latin origin. It is also found assimilated in the following forms: oc- before c (occasion); of- before f (offend); op- before p (oppress).