[1] : The Collaborative International Dictionary of English v.0.48

radiometer \ra`diom"eter\ r=a`di^o^m"-et~er, n.
   l. radius radius + -meter: cf. f. radiom`etre.
   1. naut. a forestaff.
      1913 webster

   2. physics an instrument designed for measuring the
      mechanical effect of radiant energy.
      1913 webster

   note: it consists of a number of light disks, blackened on
         one side, placed at the ends of extended arms,
         supported on a pivot in an exhausted glass vessel. when
         exposed to rays of light or heat, the arms rotate.
         1913 webster

[2] : WordNet (r) 2.0

radiometer
     n : meter to detect and measure radiant energy electromagnetic
         or acoustic

Radiometer >> R Words
Radiometer, definition of term: Radiometer
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