What does MOS stand for? For most people asking, MOS means Military Occupational Specialty, the code the Army and the Marine Corps use to name each enlisted job, from infantry to cooking to computer networks. When a soldier says "my MOS is 68W," they are telling you their job: combat medic.
The code follows a service member through training, assignments and promotions. Recruiters talk about it, enlistment contracts list it, and veterans put it on resumes so employers can see what they did. Outside the military, the same three letters show up in electronics, film sets and texting, covered further down.
Quick facts
Stands for
Military Occupational SpecialtyUsed by
US Army and US Marine CorpsType
Initialism, said M O SArmy code style
Number, number, letter, such as 11BMarine code style
Four digits, such as 0311Other branches
Air Force uses AFSC; Navy uses ratingsOther meanings
Metal oxide semiconductor; mos. for months
What does MOS stand for in the military?
Each word in the name has a job:
- Military: it applies to service members.
- Occupational: it describes the work you do, your occupation.
- Specialty: it marks a specific trained skill within that work.
So an MOS is a precise label for a trained military job. It tells leaders what a person is qualified to do and helps the service fill units with the right mix of skills. Explore more service terms in the government and military acronyms hub.
Examples of MOS codes
| Branch | Code | Job |
|---|---|---|
| Army | 11B | Infantryman |
| Army | 68W | Combat Medic Specialist |
| Army | 25B | Information Technology Specialist |
| Army | 88M | Motor Transport Operator |
| Marine Corps | 0311 | Rifleman |
In Army codes, the first two digits point to a career field and the letter narrows it to one job. Marine codes use four digits, and the first two name the occupational field. Officers and warrant officers have their own code systems as well.
How an MOS is chosen
- Take the ASVAB. The Armed Services Vocational Aptitude Battery gives line scores in areas like mechanics, electronics and general skills. Each job has minimum scores.
- Check the needs of the service. Openings depend on how many people the branch needs in each field.
- Sign a contract. In the Army, the job is often written into the enlistment contract. Marines may enlist into a broader program and get their exact code later.
- Finish training. After basic training comes job school, which the Army calls Advanced Individual Training.
Recruiter to an applicant: "Your scores qualify you for 25B or 88M. Which MOS interests you more?" The applicant is choosing between an IT job and a truck driving job.
Other branches, other names
Not every service says MOS. The Air Force and Space Force use the AFSC, or Air Force Specialty Code. The Navy and Coast Guard use ratings, such as hospital corpsman, with extra Navy Enlisted Classification codes for special skills. When veterans from different branches compare jobs, they are talking about the same idea under different labels. Related pages cover the VA, ROTC and the GI nickname for soldiers.
MOS outside the military
| Field | Meaning | Example |
|---|---|---|
| Electronics | Metal oxide semiconductor | "The circuit uses MOS transistors." |
| Film and TV | A shot filmed without sound | "Mark this take MOS." |
| Writing and texts | Mos., short for months | "Lease term: 6 mos." |
On film sets the letters are often said to come from a director's accented "mit out sound," but that origin is a popular story without firm proof. The months abbreviation has its own page: abbreviation for months.
Saying and writing MOS
Say each letter: M O S. Since the letter M is spoken "em," it takes "an": "an MOS," not "a MOS." The plural is MOSs, though many writers say "job codes" to avoid the awkward look. In a sentence: "He reclassed to a new MOS after four years," "Her MOS requires a security clearance," and "Write your MOS on the transcript request."
Questions people ask
What does MOS stand for in the Army?
It stands for Military Occupational Specialty, the job code that names each enlisted role. An example is 11B, infantryman.
Does the Air Force use MOS?
No. The Air Force uses the Air Force Specialty Code, or AFSC. The idea is the same: a code for a trained job.
Can you change your MOS?
Often yes, through a process called reclassing or lateral moves. It depends on service needs, your scores and your time in service.
Is it a MOS or an MOS?
Write "an MOS," because the letter M is spoken "em," a sound that begins with the vowel e.
What does mos mean in a text?
In casual writing, mos is short for months, as in "3 mos." It is lowercase and has nothing to do with the military code.