Abbreviations Abbreviations are selected letters (sometimes with periods) used as a shortened form of a written word or phrase. When you use abbreviations, be consistent. Abbreviate a word the same way throughout a document. Also, base your decision to abbreviate on your evaluation of the formality of the document and its intended purpose. Decide whether you will use abbreviations before you begin writing or editing.

Personal Names Personal Titles: Always use the following abbreviations instead of the full word form: Singular Plural Miss Misses Mrs. Mmes. Ms. Mses. Mr. Messrs. Dr. Drs.

Academic, Professional, and Religious Designations Attached to a Person’s Name: Many abbreviations for academic, professional, and religious designations are written with periods (but no internal spacing) when attached to a person’s name: A.S. Associate of Science B.S. Bachelor of Science D.D. Doctor of Divinity D.D.S. Doctor of Dental Science Ed.D. Doctor of Education M.A. Master of Arts M.B.A. Master of Business Administration M.D. Doctor of Medicine M.S. Master of Science Ph.D. Doctor of Philosophy R.N. Registered Nurse General Reference to Training or Occupation: When academic, professional, or religious titles are used to designate groups of people with certain kinds of training (i.e., not attached to a person’s name), the titles are often used without periods.