canny, careful, cautious, circumspect, constrained, cool, deliberate, discreet, gingerly, guarded, heedful, hesitant, incommunicable, judicious, leaving out nothing, mindful, on guard, overlooking no possibility, pawky, politic, precautional, precautionary, precautious, prudent, regardful, reserved, restrained, safe, slow to act, tentative, thorough, unadventurous, uncommunicative, undaring, unenterprising, unprecipitate, wary, watchful