acid test

American  

noun

1. a severe and conclusive test to establish quality, genuineness, worth, etc.

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acid test British  

noun

1. a rigorous and conclusive test to establish worth or value

   the play passed the critic's acid test

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acid test Idioms  

1. A decisive trial to determine worth or quality, as in Exposure to brilliant sunlight is the acid test for showing this fabric won't fade. Alluding to a 19th-century chemical test for distinguishing gold from other metals, this term was used figuratively by the early 1900s.

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Etymology

Origin of acid test

First recorded in 1890–95

Example Sentences

Single stair, and the fate of Culver City’s ordinance specifically, represents an early California acid test.

From Los Angeles Times

This will be the real acid test of Tuchel's new England and they must improve.

From BBC

But an acid test lies in wait for Celtic against Borussia Dortmund on Tuesday.

From BBC

It is this issue of pinch points which will be the acid test of the VAT policy in Edinburgh.

From BBC

Lactic acid tests have a number of important applications.

From Science Daily