Passive Smoking; Smoking, Passive 

ETS. Smoke that comes from the burning of a tobacco product and smoke that is exhaled by smokers (second-hand smoke). Inhaling ETS is called involuntary or passive smoking.

Tobacco smoking is the act of smoking tobacco products, especially cigarettes and cigars. Tobacco smoking is considered a significant cause of human health problems, especially lung cancer, emphysema, and other disorders.