1. The upper chamber of each half of the heart
   - atrium of the heart

Type of: atrium

• blue sage
• blue shark
• blue skullcap
• blue sky law
• blue star
• blue story
• blue succory
• blue thistle
• blue tit
• blue toadflax
• blue tulip
• blue vitriol
• blue wall
• blue wall of silence
• blue walleye
• blue whale
• blue-belly
• blue-black
• blue-blind
• blue-blindness
• blue-blooded
• blue-chip stock
• blue-collar
• blue-eyed
• blue-eyed African daisy