1. Water containing a substantial proportion of deuterium atoms, used in nuclear reactors
   - deuterium oxide

Type of: moderator

Encyclopedia: Heavy water

• speakerphone
• speakership
• speaking
• speaking trumpet
• speaking tube
• spear
• spear carrier
• spear thistle
• spear thrower
• spear up
• spearer
• spearfish
• spearhead
• spearhead-shaped
• spearman
• spearmint
• spearmint oil
• spearnose bat
• spearpoint
• spearwort
• spec
• special
• special act
• special agent
• Special Air Service