1. (chemistry) hydrogen
   - hydro- 
2. Water
   - hydro-

Encyclopedia: Hydr-

• ketone group
• ketonemia
• ketonic
• ketonuria
• ketoprofen
• ketorolac
• ketorolac tromethamine
• ketose
• ketosis
• ketosis-prone diabetes
• ketosis-resistant diabetes
• ketosis-resistant diabetes mellitus
• ketosteroid
• Kettering
• kettle
• kettle hole
• kettle of fish
• kettledrum
• kettleful
• Ketubim
• Keuka Lake
• keurboom
• Kevin Rudd
• Kevlar
• kewl