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Mach - definition and synonyms


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noun [countable] science     Mach pronunciation in British English
/mɑːk/    Mach pronunciation in British English
Word Forms
  1. a unit for measuring the speed of an object such as an aircraft in comparison with the speed of sound. For example, Mach 5 is five times the speed of sound.

Open Dictionary


a rise in the level of a stream or river

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