Showing that you think someone or something deserves no respect. A contemptuous look, a contemptuous laugh, a contemptuous remark — the feeling sits on the face, in the voice, in the words. It is formal but still used. In everyday talk people say looking down on someone, or talking as if they were nothing. Though actually it is about the attitude you show, not about whether the other person truly deserves it. You can be contemptuous of something perfectly decent; the word names your looking-down, not their worth. You are often contemptuous of a person or an idea. Do not mix it with contemptible: you are contemptuous; the thing you look down on may be contemptible.