Boatswain's mate (United States Navy) in the context of List of United States Navy ratings

United States Navy ratings are general enlisted occupations used by the U.S. Navy since the 18th century, which denote the specific skills and abilities of the sailor. Each naval rating has its own specialty badge, which is worn on the left sleeve of dress uniforms of enlisted personnel. U.S. naval ratings are the equivalent of military occupational specialty codes (MOS codes) used by the United States Army and the United States Marine Corps, the ratings system used by the United States Coast Guard, and Air Force Specialty Codes (AFSC) used by the United States Air Force and United States Space Force.

Ratings should not be confused with rates, which are used to identify personnel of specific a rating and pay grade. For example, if a sailor has the pay-grade of E-5 (petty officer second class) and the rating of boatswain's mate, then combining the two—boatswain's mate second class (BM2)—defines both pay grade and rating in formal address or epistolary salutation. Thus, boatswain's mate second class (BM2) would be that sailor's rate.