-hydr

dehydrated

• water has been lost
• water is added
• water has turned to ice
• water has evaporated

hydrant

• a pipe that provides water for fighting fires
• a pipe that carries sewage and waste
• a pipe in your kitchen sink
• a pipe for sending money at the bank

hydrate

• adding water to something
• taking water away from something
• freezing water into ice
• using water to make tea

hydraulic

• the name of Beyonce and Jay-Z's twin son.
• operated by the pressure of fluid
• fear of the hydra monster
• lacking or missing water

hydroplane

• a plane that runs on water
• to slide on a wet road
• the name of an epic water slide
• another name for a puddle

hydroelectric 
^{(Nominated by Kenzi & Jeff)}

• generating electricity through flowing water
• the name of a famous race horse
• the power switch turned on by rain
• rain mixed with lightning and thunder

hyrda
^{(Nominated by Gabe & Dylan)}

• a three-headed Greek dragon or snake that lives in the water
• a Greek goddess who rules over the ocean
• another form of the root word "hydr"
• a dance done in the water

hydrophobia
^{(Nominated by Konner & Zola)}

• a fear of water
• a fear of sprinklers
• a fear of synchronized swimmers
• a fear of drowning

re-hydrate
^{(Nominated by Edgar)} 

• to restore water or moisture to something
• to reheat water in the microwave
• to make beef jerky or dried apples
• to act out the water cycle

hydrogen
^{(Nominated by Ava)}

• a gas found in the atmosphere
• the name for bubbles in a bubble bath
• what is added to soda to make in bubbly
• another for steam