mysterious and known only by a few people神秘的;秘密的;晦涩难解的
He was the only person who understood all the arcane details of the agreement.他是唯一能看懂协议中所有那些晦涩难解的繁缛条文的人。
This argument may seem arcane to those not closely involved in the world of finance.对于那些不谙金融界事务的人而言,这种观点如同天书。