Definition of megavoltage in English:

megavoltage

Pronunciation /ˈmɛɡəˌvəʊltɪdʒ/ /ˈmɛɡəˌvɒltɪdʒ/

noun

Medicine
  • Voltage exceeding one million volts, specifically as used in the generation of therapeutic radiation. Chiefly attributive. Compare orthovoltage , "supervoltage".

Origin

1950s; earliest use found in Nature: a weekly journal of science. From mega- + voltage, after megavolt.