Why is the ninth month called September?
mid-15c., from Middle French radiant and directly from Latin radiantem (nominative radians) "beaming, shining," present participle of radiare "to beam, shine" (see radiation). Of beauty, etc., first attested c.1500. Related: Radiantly.
"point or object from which light radiates," 1727; see radiant (adj.). In astronomy, of meteor showers, from 1864.
radiant ra·di·ant (rā'dē-ənt)
Emitting heat or light.
Consisting of or emitted as radiation.
Noun The apparent celestial origin of a meteor shower. For example, a point in the constellation Gemini is the radiant of the Geminid meteor shower.