Real Dictionary

crude
any of a large group of nitrogenous compounds of high molecular weight that are essential constituents of all living organisms. They consist of one or more chains of amino acids linked by peptide bonds and are folded into a specific three-dimensional shap
something extracted, such as a part or passage from a book, speech, etc [...]
adjective: A crude method or measurement is not exact or detailed, but may be useful or correct in a rough, general way.
adjective: If you describe an object that someone has made as crude, you mean that it has been made in a very simple way or from very simple parts.