A name used in colorimetry for the reciprocal megakelvin (MK-1). The word is an acronym for "micro-reciprocal degree"; it is pronounced my-red, in two syllables
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}