clandestine
Word family adverbclandestinelyadjectiveclandestinenounclandestineness
clan·des·tine /klænˈdestɪn/ adjectiveadj SECRETdone or kept secret 秘密的,暗中从事的 a clandestine affair 秘密关系
clandestine meetings 秘密会议
► see thesaurus at secret Origin clandestine (1500-1600) Latin clandestinus, from clam “secretly”