Oignon pique is a French culinary term which literally means pricked onion. It is done by pricking the whole and peeled onion with a bay leaf using a whole clove as a tack. This prickling is done to add flavor to bechamel sauce and soups.
To add flavor to a bechamel sauce, the traditional method is to add a small, raw onion, studded with a couple of whole cloves and a bay leaf (make a slit in the onion to insert the bayleaf, or “nail” it on with a clove or toothpick). This onion is called “oignon pique” and is added to the milk as it is heated, and then to the sauce. When the procedure is finished, “oignon pique” is strained out.

Oignon is a French word for onion. It is pronounced as "uh nyo(n)"

Pique is a French term which means "a prick"
List of books: Oignon,pique