Synonyms and related words :
Olympian, aloof, backward, bashful, blank, chilled, chilly, cold, constrained, cool, dead, deadpan, detached, discreet, distant, dull, empty, fishy, forbidding, frigid, frosty, glassy, guarded, icy, impassive, impersonal, inaccessible, inexpressive, inscrutable, introverted, lackluster, lusterless, modest, offish, poker-faced, remote, removed, repressed, reserved, restrained, reticent, retiring, shrinking, standoff, standoffish, stolid, subdued, suppressed, unaffable, unapproachable, uncongenial, undemonstrative, unexpansive, unexpressive, ungenial, vacant, vacuous, withdrawn, wooden