Submillimeter Galaxy Definition

noun

A type of starburst galaxy that primarily emits radiation in the sub-mm/T-hertz range. Due to the extreme dustiness of the galaxy, they are visible mostly in infrared emissions at their redshift, which are subsequently redshifted into the submm/THz range by Hubble expansion .

Wiktionary

Origin of Submillimeter Galaxy

submillimeter +‎ galaxy SUBMILLIMETER GALAXY . From being a high-redshift galaxy whose emissions are primarily submillimetre -wave radiation (terahertz -radiation (T-wave /T-ray ); electromagnetic radiation with wavelengths longer than infrared and shorter than microwave/radiowave).

From Wiktionary