Wiktionary
n. (context informal English) An evaporative cooling device; a device that cools air by blowing it through or across a moist pad or membrane.
Usage examples of "swamp cooler".
Two large rooms connected by French doors, a bathroom hooked off the bedroom, a kitchen tacked onto the back of the living room, mesquite ramadas sheltering windows on all four sides against the fierce southern Arizona summer sun, with a swamp cooler on the roof instead of air conditioners.
Please God, let that funny little sound be the ancient swamp cooler or the pipes or the wind wheezing through the vent in the crawl space between the ceiling and the eaves.
The swamp cooler on the roof of the post office had lowered the interior temperature but raised the humidity, so the trade-off was just about equal.
A rusty swamp cooler sat in the room's window, unable to keep up with the dry, dusty, west Texas heat.