a cooler and more awesome word for that transparent fluid people drink with 2 Hydrogen atoms and an Oxygen atom.

Literally water. Just the fancy name for water.

A gas which is highly flammable, toxic and smelly in nature. By fermenting poo you can make some of this.
It is used to describe:
1. Some useless thing which is only used to detect danger. (It has strong odor and highly toxic)
2. Something really cringeworthy with a notable presence. (A revolting odor with toxin)
3. Really annoying thing you cannot get rid of. (It's a gas)
4. Convincing them to suicide, by intaking this gas, which will kill you in minutes.
5. Describing things that belongs to a lower class, as hydrogen sulfide is present near ocean beds to feed the organisms down there, which is low-class.
In chemistry its formula is H2S.

A nerdy phrase and a spin on the old saying airhead, used as an insult or a slight tease at someone's stupidity, and potentially at someone's short fuse as Hydrogen is a key element in the notorious Hydrogen bomb. This insult references the first element on the Periodic Table of Elements, Hydrogen (H).

Hydrogen Psychosis hahy-druh-juh n, sī'k'ōsəs: n. The Crazy Eye

A fictional type of psychosis probably based on nitrogen and hydrogen narcosis.

Symptoms of hydrogen psychosis are red eyes (hence the alternative name), confusion, disorientation, increase in heart rate, thought disorder, however it is not defined by a loss of contact with reality.

It is thought that the condition is not permanent and will pass much like the above mentioned narcosises.

Ho.
Used to avoid actually coming out and calling the person a ho to their face/behind their back. Use responsibly.

a substance that sounds creepy, but if you write the formula out, think again...