ob-
/ɒb/prefix
1
- denoting exposure or openness表示“露出”, “显露”：
obverse.
1.1
- expressing meeting or facing表示“会见”, “面对”：
occasion.
2
- denoting opposition, hostility, or resistance表示“反对”, “敌对”, “反抗”：
opponent.
2.1
- denoting hindrance, blocking, or concealment表示“障碍”, “阻止”, “隐藏”：
obviate.
3
- denoting finality or completeness表示“最终”, “完全”：
obsolete.
4
- (in modern technical words) inversely; in a direction or manner contrary to the usual（现代技术词汇中）表示“逆”, “反”, “倒”：
obconical.
USAGE
Ob- occurs mainly in words of Latin origin; it is also found assimilated in the following forms: oc- before c; of- before f; op- before p.
词源
from Latin ob 'towards, against, in the way of'.