careful nedir? careful nedir? Attentive to potential danger, error, or harm; cautious: was careful when crossing the busy street; gave a careful answer. Thorough and painstaking in action or execution; conscientious: a careful search; careful art restorers. Protective; solicitous: Be careful of his feelings. Full of cares or anxiety: "Thou art careful and troubled about many things” ( Luke 10:41).