See reticent in Webster's New World Roget's A-Z Thesaurus II
adjective
Not speaking freely or openly:
close, close-mouthed, incommunicable, incommunicative, reserved, silent, taciturn, tightlipped, uncommunicable, uncommunicative. See restraint, soundsNot friendly, sociable, or warm in manner:
aloof, chill, chilly, cool, distant, offish, remote, reserved, solitary, standoffish, unapproachable, uncommunicative, undemonstrative, withdrawn. See attitude, hot
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