(MIRD) The medical internal radiation dose committee is the society of nuclear medicine responsible for the internal dosimetry of diagnostic imaging radiopharmaceuticals.

The mediolateral view is one of the common routine views for mammography in addition to the craniocaudal view. The image receptor of the mammography system is placed lateral to the breast, and the horizontal x-ray beam is directed from medial to lateral through the breast.

(MLO) The mediolateral-oblique view is one of the standard two views of the breast. The image receptor of the mammography system is horizontally angled 30 to 60 degrees. The cassette assembly is parallel aligned to the pectoral muscle and the corner of the cassette holder fits comfortably into the axilla. The x-ray beam is directed from the superomedial to the inferolateral part of the breast.

(MeV) 1 Megaelectron volt = 1,000,000 eV

See Electron Volt.

Mesons are elementary particle which are strongly interacting bosons belonging to the hadron family. More than 140 different kinds of mesons are discovered by now. Mesons can be negatively or positively charged or neutral.