noun
non-smoking seat; non-smoking section
Refers to a seat or area where smoking is prohibited, commonly used in restaurants, trains, and other public spaces.
禁煙席でお願いします。
Non-smoking seats, please.
このレストランには禁煙席がありますか。
Does this restaurant have a non-smoking section?
喫煙席 means 'smoking seat/section', the opposite of 禁煙席.
Compound of 禁煙 (きんえん, 'no smoking') and 席 (せき, 'seat').