1. Tufted rigid North American perennial with loose clusters of white flowers
   - upland white aster

Type of: aster

• source book
• source code
• source language
• source materials
• source of illumination
• source program
• sourdine
• sourdough
• sourdough bread
• soured
• soured cream
• souring
• sourish
• sourly
• sourness
• sourpuss
• soursop
• soursop tree
• sourwood
• sous-chef
• Sousa
• sousaphone
• souse
• soused
• sousing