A megahertz is one million (or 106) hertz.
See hertz, kilohertz (one thousand hertz), gigahertz[?] (109 hertz), terahertz[?] (1012 hertz), and petahertz[?] (1015 hertz).
... instance, in the Sanskrit words for mother, matr, and father, pitr. The similarities between Latin, Greek, and Sanskrit led to the discovery of this language family by Sir ...