Mach number

noun

: a number representing the ratio of the speed of a body (such as an aircraft) to the speed of sound in a surrounding medium (such as air)

Word History

Etymology

Ernst Mach †1916 Austrian physicist

First Known Use

1937, in the meaning defined above

Time Traveler
The first known use of Mach number was in 1937

Dictionary Entries Near Mach number

Cite this Entry

“Mach number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Mach%20number. Accessed 5 Mar. 2024.

Kids Definition

Mach number

noun
: a number representing the comparison of the speed of a body to the speed of sound in the surrounding atmosphere
a Mach number of 2 indicates a speed that is twice the speed of sound

Medical Definition

Mach number

noun
: a number representing the ratio of the speed of a body to the speed of sound in a surrounding medium (as air)
a Mach number of 2 indicates a speed that is twice that of sound

More from Merriam-Webster on Mach number

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