- the nub (of something)
the central or essential point of a situation, problem, etc. 中心；要点；实质 The nub of the matter is that business is declining. 问题的核心是营业额在萎缩。 🔊🔊 She’s too selfish to help. That’s the nub. 她太自私了，无法提供帮助。那是小事。
Word Originlate 17th cent.: apparently a variant of dialect knub ‘protuberance’, from Middle Low German knubbe, knobbe ‘knob’.