1. thorough, scrupulous. Painstaking, careful, meticulous, conscientious all describe persons or behavior demonstrating attention to detail and effective task performance. painstaking stresses diligent and assiduous attention to detail in achieving a desired objective: a painstaking technician; the painstaking editing of a manuscript. Careful , the most general in sense of these words, implies serious intent to perform well and accurately whatever task one has in hand: a careful housepainter; a careful study of the social structure of gangs. Meticulous suggests extreme attention to details, especially the most minute, coupled with an almost obsessive desire to avoid error: a meticulous silversmith, every detail finished to perfection; fussily meticulous about matching shoes and clothing. Conscientious stresses scrupulous effort to obey one's sense of moral obligation to perform tasks well: a conscientious public defender; a conscientious description of the robbery.