reticent
restrained or reluctant to speak
Roots
Other words with the tac root
Tac means silent. Reticent people hold speech back, often because they are cautious, private, or unsure.
He was reticent in the meeting, but his two comments changed the decision.
Reticent is quiet with restraint inside it. A reticent person is not necessarily cold or empty; they may simply keep words behind a gate until speech feels safe or necessary.