CAS
- CAS (album)
- CAS Registry Number
- CAS latency
- CAS parameters
- CASE (disambiguation)
- CRISPR
- Calcium sulfide
- Calibrated airspeed
- California Academy of Sciences
- Calling All Stations
- Carotid stenting
- Cas (mathematics)
- Cas (name)
- Cas (people)
- Cas Cay
- Cas guava
- Casablanca American School
- Casablanca–Anfa Airport
- Cassiopeia (constellation)
- Castleton railway station
- Casualty Actuarial Society
- Caș
- Cells Alive System
- Central Authentication Service
- Certificate of Advanced Study
- Channel-associated signaling
- Chemical Abstracts Service
- Chicago, Attica and Southern Railroad
- Chief of the Air Staff (disambiguation)
- Childhood apraxia of speech
- Children's Aid Society
- Children's Aid Society (Ontario)
- Chinese Academy of Sciences
- Christchurch Adventist School
- Cigarettes After Sex
- Cinema Audio Society
- Cis-abienol synthase
- Citizens Advice Scotland
- Civil Aid Service
- Clark Ashton Smith
- Classic Arts Showcase
- Close air support
- Code Access Security
- Cognitive Assessment System
- Collision avoidance system
- Combat armor suit
- Combined Associated Schools
- Compare-and-swap
- Complex adaptive system
- Computer Aided Surgery (journal)
- Computer algebra system
- Computer-assisted surgery
- Conditional access
- Connecticut Association of Schools
- Contemporary Art Centre of South Australia
- Contemporary Art Society
- Contemporary Art Society (Australia)
- Contemporary Arts Society
- Content-addressable storage
- Controlled atmosphere stunning
- Copyright Alert System
- Cost Accounting Standards
- Council for the Advancement of Standards in Higher Education
- County Antrim Shield
- Court of Arbitration for Sport
- Covenant Aviation Security
- Cowboy action shooting
- Creativity, activity, service
- Crew-alerting system
- Critical animal studies
- Critical autism studies
- Cycle-accurate simulator
- Czech Academy of Sciences
- Democratic Party (Slovakia, 1944)
- SAS (software)
- Socialist Action Committee
- Tomáš Garrigue Masaryk
- Český atletický svaz