MCAS can mean:
- The Massachusetts Comprehensive Assessment System (a standards-based test)
- Matricula Consular de Alta Seguridad (Consular Matriculation of High Security) a.k.a. the Mexican CID card
- US Marine Corps Air Station.
- The Multnomah Community Ability Scale a standardized mental health assessment.
- Multimedia Content Adaptation System
- Multiword Compare And Swap
- Microsoft Certified Application Specialist