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

They've been far from the acid test of Scotland's true worth.

From BBC

Competitive tournament football remains the acid test - and one Tuchel is yet to pass.

From BBC

"This was the real acid test here against a team motivated to win and the holders of the competition," he insisted.

From Barron's

Sir Stephen Timms, Social Security and Disability Minister, said the government was "determined to see more disabled people in work" and that overall employment figures would be the "acid test".

From BBC

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

From Los Angeles Times