Here are the definitions matched with the corresponding terms:
- Smokeless tobacco - A type of tobacco that is not burned and can be chewed or sniffed.
- Sidestream smoke - Smoke that rises from the burning end of a cigarette, cigar, or pipe.
- Secondhand smoke - Smoke inhaled involuntarily by non-smokers; includes both mainstream and sidestream smoke.
- Stimulant - A substance that increases activity in the brain, leading to heightened alertness and energy.
- Carcinogen - A substance capable of causing cancer in living tissue.
- Nicotine - The addictive chemical found in tobacco products.
- Addictive drug - A drug that causes physical or psychological dependence in users.
- Mainstream smoke - Smoke that is exhaled by a smoker or puffed from a cigarette, cigar, or pipe.
- Tar - A thick, sticky substance produced when tobacco is burned; contains many harmful chemicals.
Feel free to arrange them in the format you need!