ob-youdaoicibaDictYouDict[ob- 词源字典]
prefix meaning "toward, against, across, down," also used as an intensive, from Latin ob "toward, to, over against, in the way of, by reason of, about, before, in front of," from PIE root *epi, also *opi "near, against" (see epi-).[ob- etymology, ob- origin, 英语词源]