conspiratorial
adjective uk/kənˌspɪr.əˈtɔː.ri.əl/ us/kənˌspɪr.əˈtɔː.ri.əl/
阴谋的;密谋的
relating to a secret plan to do something bad, illegal, or against someone's wishes
会意的；心照不宣的
showing that you share a secret
They exchanged conspiratorial glances. 他们会意地对视了一下。