: 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)
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“Mach number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Mach%20number. Accessed 31 Oct. 2025.
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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
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