Source : Webster's Revised Unabridged Dictionary (1913)

Dosimetry \Do*sim"e*try\, n. [NL. dosis dose + -metry.] (Med.)
   Measurement of doses; specif., a system of therapeutics which
   uses but few remedies, mostly alkaloids, and gives them in
   doses fixed by certain rules. -- {Do`si*met"ric}, a. --
   {Do*sim"e*trist}, n.

Source : WordNet®

dosimetry
     n : measuring the dose of radiation emitted by a radioactive
         source