I'll cite the etymology too.
[Acronym, f. the initial letters of Sw. Svenska Aktienbolaget Gasackumulator, Swedish Gas Accumulator Company, the original manufacturers.]
A proprietary name for a type of large cooking stove or range (and water-heater), burning solid fuel and (later) gas or oil. Freq. attrib., esp. as Aga cooker, stove.
Listening to: Stevie Ray Vaughan & Double Trouble - The Real Deal: Greatest Hits Vol 2 - 05 - Lenny