1. North American subspecies of tundra swan having a soft whistling note
   - whistling swan

Type of: Cygnus columbianus, tundra swan

• unsaturation
• unsaved
• unsavoriness
• unsavory
• unsavouriness
• unsavoury
• unsay
• unsayable
• unscalable
• unscathed
• unscheduled
• unscholarly
• unschooled
• unscientific
• glossiness
• Glossinidae
• glossitis
• Glossodia
• glossodynia
• glossodynia exfoliativa
• glossolalia
• glossopharyngeal
• glossopharyngeal nerve
• Glossopsitta
• Glossopsitta versicolor