[adj] not inclined to talk or give information or express opinions
Synonyms
blank, close, closelipped, closemouthed, deadpan, expressionless, guarded, impassive, incommunicado, incommunicative, inexpressive, mum, noncommittal, poker-faced, secretive, silent, tightlipped, unexpressive, unpronounceable, unrevealing, unutterable