noun
Commonly refers to a cooling-only air conditioner, as opposed to a heat pump (エアコン).
夏はクーラーをつけっぱなしにしがちだ。
In summer, I tend to leave the air conditioner on all the time.
noun
General term for a device that cools something, such as a beverage cooler or CPU cooler. Less common than the air conditioner sense.
このクーラーは缶をすぐに冷やせる。
This cooler can chill cans quickly.