Glossary of locking terms /Yale/yalelock/About_Yale/Product_Lines/Yale-padlock-in-use-IMG-3781-524x224.jpg Yale's lock jargon buster What is a mortice lock? What is a nightlatch? The language of locks can be confusing! Use Yale's jargon buster to find out exactly what different terms mean. Select the term in the list below. For additional questions please contact your local retailer.