absolute zero

• (US) IPA^(key): /ˈæb.səˌlut ˈzi.ɹoʊ/, /ˌæb.səˈljut ˈzi.ɹoʊ/

• Audio (General Australian):

  (file)

absolute zero (plural absolute zeros)

1. (physics) The coldest possible temperature, zero on the Kelvin scale, or approximately −273.15 °C, −459.67 °F; total absence of heat; temperature at which motion of all molecules would cease. [First attested in the early 19^th century.]
2. (slang) A person or thing of absolutely no consequence.

•   absolute zero on Wikipedia.Wikipedia