The only Oxford definition of this is "oil-cake" some sort of leftover from oil-processing. But I found the word in a synonym list of words for "opening", "mouth" and similar. So I am not getting the sense of the word, and do not understand why Oxford left it out. Roots of words help me get the meanings, but I am apparently overlooking the sense. В каком смысле этого слова? избоина
Maybe give me some simple sentences? Thanks