Non/nɑːn/ Definition 1 of 4Pro Tip 1/3Contrary Indicator Shows that something is the opposite of the norm or expectation. While most companies aim for profit, his business is nonprofit. Pro Tip 2/3Lack of Action Indicates that a usual action or process doesn't occur. The festival was nonstop; it continued day and night without pause. Pro Tip 3/3Safety Assurance Assures that a product or substance does not cause harm. This cleaning spray is nontoxic, making it safe for children and pets.