knock out

Idioms  

1. Also, knock out cold . Render unconscious by a blow or some other means. For example, It was just a swinging door, but it knocked her out , or Just one of those sleeping pills can knock you out cold . [Late 1500s]

2. Make tired, exhaust, as in That sightseeing tour knocked me out .

3. Render useless or inoperative, as in The storm knocked out the power .

4. See knock off , def. 2.

5. See knock oneself out .

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Example Sentences

So don’t expect $28 tickets for finals or knock out rounds to the most in-demand sports including women’s artistic gymnastics, basketball, swimming or track and field to be sold at all.

From Los Angeles Times • Apr. 15, 2026

League One side Port Vale knock out Premier League team Sunderland to reach the FA Cup quarter-finals for the first time since 1954.

From BBC • Mar. 8, 2026

The attacks do more than just knock out the power -- they also sap the morale, particularly of the communities of workers and families that have been built around the plants.

From Barron's • Feb. 10, 2026

Second, do we need to have the ability to knock out all of their missile sites in order to deter nuclear war?

From Slate • Feb. 3, 2026

The VC would try to knock out communications.

From "Boots on the Ground: America's War in Vietnam" by Elizabeth Partridge