cosh

¹ American  

[kosh] / kɒʃ /

noun

1. a blackjack; bludgeon.

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verb (used with object)

• coshes,
  present (3rd person singular)
• coshed,
  past participle,  past
• coshing
  present participle

1. to hit on the head with a cosh.

cosh ² American  

[kosh] / kɒʃ /

noun

Mathematics.

1. hyperbolic cosine.

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cosh ¹ British  

/ kɒʃ, ˈkɒsˈeɪtʃ /

noun

1. hyperbolic cosine; a hyperbolic function, cosh z = 1/ 2 (e z + e –z ), related to cosine by the expression cosh i z = cos z, where i = √–1

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cosh ² British  

/ kɒʃ /

noun

1. a blunt weapon, often made of hard rubber; bludgeon

2. an attack with such a weapon

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verb

1. to hit with such a weapon, esp on the head

cosh Scientific  

1. Abbreviation of hyperbolic cosine

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Other Word Forms

Inflected Forms

Participles

• coshing
  present
• coshed
  past

Conjugated Forms

Present

• cosh
  simple
• coshes
  simple
• have coshed
  perfect
• has coshed
  perfect
• am coshing
  progressive
• are coshing
  progressive
• is coshing
  progressive
• have been coshing
  perfect progressive
• has been coshing
  perfect progressive

Past

• coshed
  simple
• had coshed
  perfect
• was coshing
  progressive
• were coshing
  progressive
• had been coshing
  perfect progressive

Future

• will cosh
  simple
• will have coshed
  perfect
• will be coshing
  progressive
• will have been coshing
  perfect progressive

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Etymology

Origin of cosh¹

First recorded in 1865–70; of uncertain origin; perhaps from Romani kosh, koshter “piece of wood,stick,” akin to Sanskrit kāṣṭham

Origin of cosh²

First recorded in 1870–75; cos(ine) + h(yperbolic)

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Example Sentences

See Examples For:

cosh coshing

Reform punchy but feeling under the cosh and plenty of the others scrapping for attention too.

From BBC ● Aug. 14, 2026

The dynamics of the Japanese yen carry-trade, however, a trading strategy where investors short low-yielding yen assets to buy higher-yielding assets elsewhere, have kept it under the cosh for most of the past 15 years.

From MarketWatch ● Aug. 3, 2026

"There's no two ways about it - we were under the cosh," McInnes admitted.

From BBC ● Apr. 11, 2026

Four-time major champion Sinner was imperious and looked unflustered on the few occasions that the aggressive Shelton put him under the cosh.

From Barron's ● Jan. 28, 2026

"Py cosh, I not cook chuck for you fellers ven I'm sick," he mumbled dazedly.

From The Happy Family by B. M. Bower

It is impossible to keep the South Africa's coshing scrum power out of the game, however.

From BBC ● Sep. 5, 2026

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Related Words

• bash
• bludgeon
• clobber
• pummel
• whack

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