What is the origin of denim?

When you hear the word denim, you immediately think of jeans. This sturdy cloth that both young and old wear nowadays was originally made in the town of Nimes in France. I understand the name is pronounced like the word neem. The tough cloth material when it was introduced was not called denim but serge. It was often referred to as serge. It was often referred to serge de Nimes, meaning serge of Nimes with the passage of time, the name of the cloth was shortened to deim. Sailors from genoa, a seaport in Italy, made pants from denim. Since the trousers lasted for a very long time, they were affectionately called Genoese. The name was later shortened to geans from which we get the word jeans.