con·sci·en·tious / ˌkänchēˈenchəs/ • adj. (of a person) wishing to do what is right, esp. to do one's work or duty well and thoroughly: a conscientious and hardworking clerk. ∎ (of work or a person's manner) showing such an attitude. ∎ relating to a person's conscience.DERIVATIVES: con·sci·en·tious·ly adv.con·sci·en·tious·ness n.