Adjective:
relating to the peripheral and unimportant aspects of life;a hole-and-corner life in some obscure community
conducted with or marked by hidden aims or methods;clandestine intelligence operations
cloak-and-dagger activities behind enemy lines
hole-and-corner intrigue
secret missions
a secret agent
secret sales of arms
surreptitious mobilization of troops
an undercover investigation
underground resistance
近义词 secret秘密hidden隐藏的private私人的secretive秘密的hush-hush秘密的underground地下的hugger-mugger秘密的surreptitious暗中进行的hole-in-corner偷偷摸摸的undercover从事秘密工作的…cloak-and-dagger有关阴谋或间谍的…clandestine秘密的常指违法的行为…
用作形容词She is increasingly paranoid and secretive.她是越来越害怕和秘密的。
And scientists are now beginning to recognize these telltale signs.科学家们现在开始对这些泄露黑洞秘密的征兆有所认识。