The Collaborative International Dictionary of English v.0.48:
OAS \OAS\ n.
   The Organization of American States an international
   association of countries in the Western hemisphere. It was
   created in 1948 to promote military and economic and social
   and cultural cooperation. [acronym]
   Syn: Organization of American States.
        [WordNet 1.5]
WordNet (r) 3.0 (2006):
OAS
    n 1: an association including most countries in the western
         hemisphere; created in 1948 to promote military and
         economic and social and cultural cooperation [syn:
         Organization of American States, OAS]
V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):
OAS
       Office Automation System