Clandestine (adjective)
Done or kept in secret, sometimes to conceal an illicit or improper purpose.
“covert|furtive|hush-hush|secret|secretive|undercover|Thesaurus:covert”
“clandestine military operations”
Clandestine (adjective)
Not recognized as a regular member.
Tryst (noun)
A prearranged meeting or assignation, now especially between lovers to meet at a specific place and time.
Tryst (noun)
A mutual agreement, a covenant.
Tryst (verb)
To make a tryst; to agree to meet at a place.
Tryst (verb)
To arrange or appoint (a meeting time etc.).
Tryst (verb)
To keep a tryst, to meet at an agreed place and time.
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