out cold

Idioms  

1. Also, out for the count; out like a light. Unconscious; also, asleep. For example, He crashed into the wall and was out cold, or Willie punched him too hard, and he was out for the count or Don't call Jane; she's out like a light by ten every night. The adjective cold refers to the lack of heat in a dead body and has been used to mean “unconscious” since the second half of the 1800s. The first variant comes from boxing, where a fighter who is knocked down must get up before the referee counts to ten or be declared defeated; it dates from about 1930. The last variant alludes to turning out a light and dates from the first half of the 1900s.

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Example Sentences

On one outing near Carter’s home in central Illinois, a flying carp knocked his friend out cold.

From The Wall Street Journal • Apr. 8, 2026

The new study shows that dark matter does not necessarily need to start out cold.

From Science Daily • Jan. 15, 2026

Some found that shocking but that's how it is when a fighter gets knocked out cold.

From BBC • May 8, 2024

Just when it seems that B.J. is out cold, his eyes fly open and he reaches, grabs, twists.

From New York Times • Jul. 16, 2023

One minute she was sorting campus mail, the next minute she was out cold.

From "The Namesake" by Jhumpa Lahiri