Dry ice is frozen carbon dioxide (CO2). It is called dry ice because it sublimates, i.e. it transits to vapour without a prior transition to liquid state. It is a convenient refrigerant because it sublimes at -78 °C.
Citing this page:
Generalic, Eni. "Dry ice." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.