What rule applies most closely to this word -deplor?

The Word "deplor" is a root that relates to expressing disapproval or regret. It derives from the Latin "deplorare," meaning to lament or mourn. In English, this root is commonly associated with Words like "deplore," which conveys a strong sense of disapproval or sorrow regarding a situation or action. The rule that applies here is the use of the root in forming Words that express negative feelings or reactions.