1. smoke that comes directly from the burning end of a cigarette, cigar, or pipe, rather than being inhaled and exhaled by the smoker
Usage: medical; health
2. a smaller stream that flows into or branches off from a main stream

1. relating to or being smoke that comes directly from burning tobacco
Usage: medical; health

Examples

• Sidestream smoke contains higher concentrations of certain toxins than mainstream smoke.
• The restaurant banned smoking to protect customers from sidestream smoke exposure.
• A small sidestream branched off from the main river near the bridge.
• The creek was fed by several sidestreams flowing down from the mountains.
• Sidestream emissions are particularly harmful to nonsmokers in enclosed spaces.
• They followed the sidestream upstream to find its source.
• Studies show that sidestream smoke poses serious health risks to bystanders.