Synonyms 1. watchful, guarded, chary, circumspect. Careful,cautious,discreet,wary imply a watchful guarding against something. Careful implies guarding against mistakes, by paying strict and close attention to details, and, often, trying to use good judgment: He was careful to distinguish between them. Cautious implies a fear of some unfavorable situation and investigation before coming to conclusions: cautious about investments. Discreet implies being prudent in speech and action and being trustworthy as a confidant: discreet in manner, in keeping secrets. Wary implies a vigilant lookout for a danger suspected or feared: wary of polite strangers. 2. meticulous, discerning. 2, 3.See painstaking.3. conscientious. 4. thoughtful, concerned, solicitous, attentive, heedful, regardful.
O.E. cearful "mournful," also "full of care or woe," "full of concern" (for someone or something), thus "applying attention, painstaking, circumspect;" from care + -ful.