radiation source; source of radiation
Technical term used in physics, nuclear engineering, and radiation safety to refer to any object or material that emits ionizing radiation.
This device measures the radiation emitted from the radiation source.
Sealed radiation sources are widely used in medicine and industry.
radioactive small source
Compound of 線 (sen, 'ray' or 'radiation') and 源 (gen, 'source'). A straightforward technical coinage.