Marijuana grown indoors using a hydroponics system (tubes and filters with water and fertilizers). To correct the first definition, NO marijuana causes mental problems - but it does get you really high.
I couldn't find any hydro for the weekend, so I had to settle for some reg.
by Johnnybong May 19, 2005
Get the mug
Get a hydro mug for your cat Helena.
Hydroponically grown marijuana of good quality. Often called "hyge" for short.
Also used to describe the hydroponic setup used to grow the weed.
"I had a few cones of hydro after smoking bush for a week, it put me on my ass!"
"I'm going to get a new hydro setup tommorow."
by Diego July 08, 2003
Get the mug
Get a hydro mug for your guy Zora.
Hydro is a better type of marijuana because you will get a more enjoyable high when smoking it. For example smoking regular weed will make you tired.
You will know that you are smoking real hydro because the ash will be pure white, not grey like shitty weed.
by b rolls June 27, 2005
Get the mug
Get a hydro mug for your Facebook friend Manafort.
Canadian slang for electricity, due to the high usage of hydroelectric power and the fact that most of the electric companies have "hydro" in their names.
I had to pay the hydro bill.

Hydro Quebec, Manitoba Hydro
by cjohnson October 29, 2007
Get the mug
Get a hydro mug for your dog James.
short for hydrocodones, or Loritabs. some people pop them, some break up and snort. stimulates the opate receptors of the mind. fairly easy to get. codine is also found in some types of perscription syrups.
Thanks for the hydros, my night at work will be much better now!
by that white kid... March 10, 2006
Get the mug
Get a hydro mug for your friend Zora.