Top Definition
Dihydrogen Monoxide (DHMO) is a colorless and odorless chemical compound, also referred to by some as Dihydrogen Oxide, Hydrogen Hydroxide, Hydronium Hydroxide, or simply Hydric acid. Its basis is the unstable radical Hydroxide, the components of which are found in a number of caustic, explosive and poisonous compounds such as Sulfuric Acid, Nitroglycerine and Ethyl Alcohol.
For more detailed information, including precautions, disposal procedures and storage requirements, refer to the Material Safety Data Sheet (MSDS) for Dihydrogen Monoxide.
...Dihydrogen monoxide is water/H20.
Dihydrogen Monoxide as a toxic or carcinogenic substance (as it does with better known chemicals such as hydrochloric acid and saccharine), DHMO is a constituent of many known toxic substances, diseases and disease-causing agents, environmental hazards and can even be lethal to humans in quantities as small as a thimbleful.
by brendan December 09, 2004
Dihydrogen Monoxide is a prevalent compound that is the key ingredient in most pesticides. DHMO contributes to environmental hazards such as acid rain, the greenhouse effect, and soil erosion. DHMO poisoning causes a sometimes fatal electrolyte imbalance in the bloodstream, and can cause excessive sweating, increased urination, and sometimes vomiting. Dihydrogen Monoxide also reacts explosively with alkaline earth metals such as lithium, sodium, potassium etc.
Prolonged, unprotected exposure to solid DHMO, or inhaling it can be fatal.
Despite these dangers, DHMO is used ubiquitously by industries, and is readily available to the public.
Join the fight, and help get this troublesome, and potentially lethal chemical banned.
by October 01, 2006
water, H2O
dihydrogen monoxide: It's more commonly known as water. You know, the substance that every single living being relies on to survive? The origins of this item are multifold, from flyers circulated at the University of California at Santa Cruz in 1989 (so 20th century!) to a junior high school student who surveyed 50 classmates in 1997 and got 43 of them to sign his petition to ban the chemical. He then won a prize at his science fair for his project, called "How Gullible Are We?" Several Web pages touting the chemical's dangers are still live. Don't feel too bad if you've ever fallen victim to this hoax; even a government official in New Zealand took the bait last year.
by l333 August 28, 2008
a substance that sounds creepy, but if you write the formula out, think again...
Bob: di-Hydrogen monoxide is gonna destroy the world

Joe: idiot... (takes a large gulp of water)
by dab52 December 30, 2011
Evidently really baaaad stuff.
In today's lab, you're gonna be working with dihydrogen monoxide. Now in large amounts, it could cause suffocation and death. If the subtance is heated, it could cause severe burns. Cold versions of this substance can also cause frostbite. Handle this lab with extreme caution, please.
by Ichigo69 November 01, 2009
Dihydrogen monoxide (DHMO) is a combination of 2 hydrogen and 1 oxygen (di = 2, mon = 1), which creates H2O. It is a completely safe element, but a hoax that was created in the 1990's as an April Fools joke got popular that said that DHMO was a chemical that was a substance that was contained in things such as acid rain, nuclear power plants, etc.
John: "Have you heard about the chemical Dihydrogen monoxide? I read that it was really dangerous and it's even in our water and food!"

Steve: "No, that is just water. Do more research and don't believe everything you read online."
by Ay Lmao October 20, 2015

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