Caustic soda is the trade name of Sodium Hydroxide (NaOH), which is an agent used to clear drains of junk that has gotten there someway or other. It is allso a cheap source of hydrogen gas.

Put some in a bottle along with tin foil, add water and pull a balloon over the top. Watch as it inflates and there, you have a balloon o' hydrogen.

It can manipulate your voice in a similar way to helium, but it's cheaper, or when mixed with oxygen and lit it can manipulate other people's voices into sounding as though they're muted, along with sounds of any sort really.

Warning: Caustic soda is very caustic, as one might understand. Getting it in your eyes is actually worse than getting a strong acid there.
Allso, a mixture of hydrogen and oxygen is quite volatile.

Disclaimer
You didn't hear this from me.
After my girlfriend took a shower, the drain was clogged with hair. I can't believe she has that much, or had. It took all my caustic soda to get rid of, so now I can't preform as Mickey the Mouse for the children.
by Chemical Arvid March 29, 2008
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To make comments on the different ways people are annoying, disgusting and/or just plain weird.
"Models walking into the Community room. Each one looks hungrier and bitchier than the next. You know how you're not supposed to yell FIRE in a crowded theater? I bet if I yelled CHEESEBURGER it would have the same effect."

Wow how caustically observant.
by Silently Observant November 17, 2012
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A verbose young lady noted for her acerbic wit and driving debate.
The Caustic Git tore him a new one when he tried to tell her to "cheer up."
by The Git herself February 10, 2004
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A book that rivals the bible in manner of words and format, but is done in an agnostic editorial style.
Man, don't preach to me till your read the Agnostic Book of Caustic.
by Dr Michael Shriverhelm February 15, 2014
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