Definition from Wiktionary, the free dictionary
Alternative forms 
Acronym used in the United States military: “Absent WithOut Leave”.
AWOL (not comparable)
AWOL (plural AWOLs)
- (military) Absence without proper authority from the properly appointed place of duty, or from unit, organization, or other place of duty at which one is required to be at the time prescribed.
- (military) A person who holds AWOL status.
- (generic) Somebody who is absent without permission.
- (figuratively) Someone or something missing.
military: absence without proper authority
generic: one who is absent without permission
figurative: someone or something missing
See also 
- UA – Unauthorized Absence