United States Amy Rank Abbreviations and Acronyms

1. OMC
   OPTICALMAN CHIEF PETTY OFFICER
2. OMCM
   OPTICALMAN MASTER CHIEF PETTY OFFICER
3. OMCS
   OPTICALMAN SENIOR CHIEF PETTY OFFICER
4. OMSA
   OPTICALMAN SEAMAN APPRENTICE
5. OMSN
   OPTICALMAN SEAMAN
6. OMSR
   OPTICALMAN SEAMAN RECRUIT
7. OS
   Ordinary Seaman
8. OS
   Officer'S Steward
9. OS2
   OPERATIONS SPECIALIST PETTY OFFICER 2ND CLASS
10. OS2
    ORDINARY SEAMAN 2ND CLASS
11. OS2
    OFFICER'S STEWARD 2ND CLASS (NON PETTY OFFICER
12. OS3
    OFFICER'S STEWARD 3RD CLASS (NON PETTY OFFICER)
13. OS3
    OPERATIONS SPECIALIST PETTY OFFICER 3RD CLASS
14. OSC
    OPERATIONS SPECIALIST CHIEF PETTY OFFICER
15. OSCM
    OPERATIONS SPECIALIST MASTER CHIEF PETTY OFFICER
16. OSCS
    OPERATIONS SPECIALIST SENIOR CHIEF PETTY OFFICER
17. OSSA
    OPERATIONS SPECIALIST SEAMAN APPRENTICE
18. OSSN
    OPERATIONS SPECIALIST SEAMAN
19. OSSR
    OPERATIONS SPECIALIST SEAMAN RECRUIT
20. OSTD
    Officer'S Steward

Last updated: May 24, 2020 — Total entries: 3,362