Radiator \Ra"di*a`tor\, n.

1. Any of various devices for cooling an internal substance by radiation, as a system og rings on a gun barrel for cooling it, or a nest of tubes with large radiating surface for cooling circulating water, as in an automobile.

2. (Wireless Teleg.) An oscillator.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Radiator \Ra"di*a`tor\, n. That which radiates or emits rays, whether of light or heat; especially, that part of a heating apparatus from which the heat is radiated or diffused; as, a steam radiator.

Source: Webster's Revised Unabridged Dictionary (1913)