ultracold

/ˌʌltrəˈkoʊld/
adjective
  1. Extremely cold; often used in science to describe temperatures near absolute zero, or informally to mean very cold.
    • The lab uses ultracold lasers to cool atoms to near absolute zero.
    • The ultracold storage unit keeps the vaccines at a stable low temperature.
    • We had an ultracold winter this year, with temperatures dropping to -40 degrees.
Antonyms
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