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: 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
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 30 Nov. 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
Britannica.com: Encyclopedia article about Mach number
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