Cas
Cas may refer to:
- Caș, a type of cheese made in Romania
- Čas (1886–) Czech magazine associated with Tomáš Garrigue Masaryk
- Čas (19 April 1945–February 1948), the official, daily newspaper of the Democratic Party of Slovakia
- CAS, a 2018 album by Lúnasa, an Irish Celtic band
- Cas (people), an ancient people near the Caspian Sea
- Cas (name), a list of people (and a mythological hero) with the given name, nickname or surname
- Cas guava (Psidium friedrichsthalianum), a Costa Rican guava species
- Cas Cay, an island in St. Thomas, United States Virgin Islands
- Cassiopeia (constellation), standard astronomical abbreviation
- Castleford, town in West Yorkshire know colloquially as Cas
- CRISPR-associated proteins, proteins involved in prokaryotic antiviral defense and gene editing
- Chemical Abstracts Service (CAS)
- CAS Registry Number, a unique identification number, assigned by the Chemical Abstracts Service in the US to every chemical substance
- Cas (mathematics)