from The Century Dictionary.
- noun An instrument consisting of a bolometer in combination with a spectroscope, used in the study of the distribution of heat in the solar spectrum and in similar investigations.
from the GNU version of the Collaborative International Dictionary of English.
- noun (Physics) A combination of spectroscope and bolometer for determining the distribution of energy in a spectrum.
Sorry, no etymologies found.
An important step towards the solution of this question had been taken as early as 1886 by Langley who, with his famous spectrobolometer, investigated the distribution of radiation in the spectrum of a number of heat sources of high and low temperature.