REV meaning in Academic & Science ?

The Reverend is an honorific style most often placed before the names of Christian clergy and ministers. There are sometimes differences in the way the style is used in different countries and church traditions. The Reverend is correctly called a style but is often and in some dictionaries called a title, form of address, or title of respect. The style is also sometimes used by leaders in non-Christian religions, such as Judaism.

The term is an anglicisation of the Latin reverendus, the style originally used in Latin documents in medieval Europe. It is the gerundive or future passive participle of the verb revereri ("to respect; to revere"), meaning "[one who is] to be revered/must be respected". The Reverend is therefore equivalent to The Honourable or The Venerable. It is paired with a modifier or noun for some offices in some religious traditions: Lutheran archbishops, Anglican archbishops, and most Catholic bishops are usually styled The Most Reverend (reverendissimus); other Lutheran bishops, Anglican bishops, and Catholic bishops are styled The Right Reverend.

With Christian clergy, the forms His Reverence and Her Reverence are also sometimes used, along with their parallel in direct address, Your Reverence. The abbreviation HR is sometimes used.