An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A suffix used principally in the names of various devices and instruments (klystron; magnetron; cyclotron; synchrotron).

Perhaps a shortening of electron with accidental allusion to the Gk. instrumental suffix -tron, as in arotron "plough;" akin to O.E. -thor, suffix denoting an instrument; L. -trum; Skt. -tra.