mach
1 Americannoun
noun
abbreviation
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machine.
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machinery.
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machinist.
noun
noun
Usage
How fast is Mach 1? A Mach number is the ratio of an object's speed in a given medium to the speed of sound in that medium. Mach 1, then, is the speed of sound, around 761 mph at sea level on a standard day. The term is also used as a metaphor for high speeds more generally. How to pronounce Mach 1[ mahk wuhn ]
Etymology
Origin of mach
After Ernst Mach
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
After the results, Bhattacharya said, the BJP would send "different kinds of small fish" to Banerjee's house and invite her party workers over for mach bhaat, Bengali for fish and rice.
From BBC • Apr. 20, 2026
Air Force Captain Kristin "BEO" Wolfe performs the "high-speed pass" maneuver at approximately .95 mach, which is just below the speed of sound, at the 2020 Fort Lauderdale Air Show in Fort Lauderdale, Florida, U.S.
From Reuters • Nov. 16, 2021
I will be curious to see what mach his framework has achieved by then.
From Forbes • Mar. 10, 2013
A "mach meter," an aerial speedometer, in view of passengers in the first few rows reached mach 1.
From Time Magazine Archive
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In this capacity he soon left the “regular” men far behind, though they in their turn were very mach disposed to treat the Killingworth brakesman as no better than a quack.
From Lives of the Engineers The Locomotive. George and Robert Stephenson by Smiles, Samuel
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.