LOP means Loss of Privileges. We don’t see this one too often, and so it can stump people when they do see it as it isn’t always clear from the context what this might refer to. An LOP generally is the result of a disciplinary case. Sometimes loss of privileges are also described as, for example, 45/45/45, which means 45 days loss of access to three types of “privileges” such as recreation, commissary, and out-of-cell time or access to certain property.