American English

Definition of Mach noun from the Oxford Advanced American Dictionary

 

Mach

 noun
noun
NAmE//mɑk//
 
,
 
[uncountable]
 
jump to other results
(often followed by a number) a measurement of speed, used especially for aircraft. Mach 1 is the speed of sound. a fighter plane with a top speed of Mach 3 (= 3 times the speed of sound)
See the Oxford Advanced Learner's Dictionary entry: Mach