from
The Collaborative International Dictionary of English v.0.48
Radiometer \Ra`di*om"e*ter\ (r[=a]`d[i^]*[o^]m"[-e]*t[~e]r), n.
[L. radius radius + -meter: cf. F. radiom[`e]tre.]
1. (Naut.) A forestaff.
[1913 Webster]
2. (Physics) An instrument designed for measuring the
mechanical effect of radiant energy.
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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.
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