1951 28 109/2 A triggering pulse of 3 volts is effective if it lasts 20 milli-microseconds.
1964 F. L. Westwater viii. 127 Switching speeds of a few millimicroseconds appear possible.
1980 S. J. Gould (1982) vii. 83 In this millimicrosecond, we have transformed the surface of our planet.