(idiomatic) Synonym of throw cold water on (“to belittle or dismiss”).

(transitive, idiomatic) (of an achievement, emotion, idea, suggestion, etc.) to belittle or dismiss; to cast doubt upon; to debunk.

(espionage) Of a spy: to return home after having gone undercover in enemy territory. / (by extension) To gain widespread acceptance in a group or society, especially where there was not any before.

(obsolete) Dead.

(simile, colloquial, vulgar, humorous) Very cold.

I am suffering from a cold.

Dark matter traveling at classical, non-relativistic speeds

To ignore someone insultingly or slightingly.

(idiomatic, colloquial) The time of occurrence of an event that will never happen.

A disease of humans characterized by sudden hemoglobinuria, typically after exposure to cold temperatures.