also: きつえんしょ
noun
smoking area; smoking corner
A designated place for smoking, often found in public facilities, stations, or offices.
駅の喫煙所はどこですか。
Where is the smoking area at the station?
このビルには喫煙所がありません。
There is no smoking area in this building.
喫煙室 is a smoking room, typically an enclosed indoor space, while 喫煙所 can be an open or semi-open designated area.
Compound of 喫煙 (smoking) and 所 (place).