1. Old World aspen with a broad much-branched crown; northwestern Europe and Siberia to North Africa
   - quaking aspen, Populus tremula

Type of: aspen

• positive
• positive charge
• positive chemotaxis
• positive correlation
• positive degree
• positive feedback
• positive fraud
• positive identification
• positive magnetic pole
• positive muon
• positive pole
• positive reinforcer
• positive reinforcing stimulus
• positive stimulus
• positively
• positively charged
• positiveness
• positivism
• positivist
• positivistic
• positivity
• positron
• positron emission tomography
• positron emission tomography scanner
• posology