A mortise lock is a type of lock that is designed to fit into a mortise, which is a hole that is cut into the edge of a door. If you are looking for synonyms for the word "mortise lock," there are several options available. Some of the most common synonyms for a mortise lock include cylinder lock, deadbolt lock, rim lock, and padlock. Each of these types of locks varies in design, but they all function to provide security by locking a door or other type of entryway. When choosing the right lock for your needs, it's important to consider the level of security you need and the specific features of each type of lock to ensure that you are getting the best possible protection for your property.