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acid test

A conclusive test. The phrase comes from the 19th-century practice of testing metals in nitric acid to determine if they contained gold. Restructuring the organization will be the acid test that determines whether or not it can survive the sudden downturn in the economy.
See also: acid, test

be on acid

To be under the influence of lysergic acid diethylamide (LSD), a powerful psychedelic drug commonly known as "acid." A lot of my friends like being on acid, but it just makes me feel really tense and paranoid.
See also: acid, on

come the acid

To be unpleasant or offensive, usually due to speaking in a caustic or sarcastic manner. Often followed by "with (someone)." Don't come the acid with me, son, or I'll knock you upside the head. I try to avoid her whenever I can, for she's far too quick to come the acid.
See also: acid, come

drop acid

slang To ingest the psychedelic drug lysergic acid diethylamide (LSD, or "acid"). I had a real bad trip last night. I'll never drop acid again. A lot of my friends like dropping acid, but it just makes me feel really tense and paranoid.
See also: acid, drop

on acid

Under the influence of lysergic acid diethylamide (LSD), a powerful psychedelic drug commonly known as "acid." The man was reportedly on acid when claimed he could fly and tried to jump off the building.
See also: acid, on

put the acid on (someone)

To beg, importune, or proposition (someone) for something, such as a money loan, a favor (sexual or otherwise), or information. Primarily heard in Australia, New Zealand. My no-account brother-in-law is always putting the acid on for a money loan—which, I'll add, he has never once paid back. It's like he's surprised when women in a random bar don't all come up putting the acid on him.
See also: acid, on, put
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

acid test

Fig. a test whose findings are beyond doubt or dispute. The senator doesn't look too popular just now, but the acid test will be if he gets reelected.
See also: acid, test
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.

acid test

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.
See also: acid, test
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

the acid test

COMMON If you call something the acid test, it will prove how effective or useful something is. The acid test for the vaccine will be its performance in the south where the disease is more widespread. So far, I don't feel too bad but I'm waiting for my first really stressful day when things go wrong. That will be the real acid test. Note: Nitric acid can be used to test whether a metal is pure gold because it damages most metals but does not affect gold.
See also: acid, test
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012

the acid test

a situation or event which finally proves whether something is good or bad, true or false, etc.
The original use of the phrase was to describe a method of testing for gold with nitric acid (gold being resistant to the effects of nitric acid).
1990 Which? These deals are designed to encourage impulse buying, so the acid test is whether you would have bought anyway.
See also: acid, test

come the acid

be unpleasant or offensive; speak in a caustic or sarcastic manner.
See also: acid, come

put the acid on someone

try to extract a loan or favour from someone. Australian & New Zealand informal
See also: acid, on, put, someone
Farlex Partner Idioms Dictionary © Farlex 2017

the ˌacid ˈtest (of something)

(also the ˈlitmus test especially in American English ) a situation which finally proves whether something is good or bad, true or false, etc: They’ve always been good friends, but the acid test will come when they have to share a flat.Both these expressions originally referred to chemical tests. The acid test uses nitric acid to test if something is made of gold. The litmus test uses litmus paper to test for acids and alkalis.
See also: acid, test
Farlex Partner Idioms Dictionary © Farlex 2017


n. lysergic acid diethylamide (LSD). (Drugs.) Freddy got hold of some bad acid and freaked out.
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

acid test, the

A conclusive trial to establish the truth or worth of something or someone. The term comes from a test long used to distinguish gold from copper or some other metal. Most corrosive acids do not affect gold, but a solution of nitric acid and hydrochloric acid dissolves the metal. Used literally by jewelers in the late nineteenth century, the term soon was employed figuratively, by U.S. president Woodrow Wilson among others.
See also: acid
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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References in periodicals archive ?
This mutant showed increased oleic acid levels in seeds (535 g [kg.sup.-1] compared with 154 g [kg.sup.-1] in the wild type), roots (559 g [kg.sup.-1] compared with 68 g kg in the wild type), and leaves (209 g [kg.sup.-1] compared with 23 g [kg.sup.-1] in the wild type).
During the determination of oil composition, oleic, linoleic and stearic acid contents were measured.
Imported Group II base Oil (LP-70), Locally Group I base Oil (65NHVI also known as Spindle oil, Pakistan national refinery limited), Sulphuric acid, Bleaching earth clay (Bleaching earth clay also known as Bentonite clay, Tahir Asad Industries (Pvt.) Ltd).
The major companies involved in the manufacturing and production of Palmitic acid are AkzoNobel N.V., H.
Among the acids in coffee, chlorogenic acid is of further significant importance.
Desorption of Cd and Pb in the presence of organic acid and amino acid
The new technology reduces the volume of sulfuric acid used in the resist stripping process by 70% and totally eliminates the use of hydrogen peroxide.
Intake of folic acid, or folate, is higher in the United States than in most countries in part because U.S.
Flaxseed oil is known to be a source of alpha-linolenic acid, an omega-3 fatty acid that can be converted to another omega-3 fatty acid called eicosapentaenoic acid (EPA) and that may reduce the risk of death from heart disease.
Domoic acid, a naturally occurring marine toxin, causes acute symptoms of diarrhea, vomiting, seizures, and memory loss in people sickened by eating contaminated shellfish.
More recently they have speculated that acid rain robs trees of this vital nutrient by leaching it from the soil and by mobilizing aluminum, which interferes with calcium uptake by roots.