Word Study
[2x]
: MÜ Mä Mæ Mé Mê Mö Mœ M- M. M1 M2 M3 M< Ma Mb Mc Md Me Mf Mg Mh Mi Mk Ml Mm Mn Mo Mp Mr Ms Mt Mu Mv Mw Mx My
mach
OXFORD DICTIONARY
mach, n. (in full Mach number) the ratio of the speed of a body to the speed of sound in the surrounding medium.
Idiom
Mach one (or two etc.) the speed (or twice the speed) of sound.
Etymology
E. Mach, Austrian physicist d. 1916
For further exploring for "mach" in Webster Dictionary Online