OXYGENATE

v. combine or infuse with oxygen (often about fuel in order to make it burn more efficiently)

Oxygenated substances have been infused with oxygen. The term usually refers to oxygenated fuels. Oxygenates are usually employed as gasoline additives to reduce carbon monoxide that is created during the burning of the fuel. Some oxygenates such as MTBE have been found to have contaminated groundwater, mostly through leaks in underground gasoline storage tanks.
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Verb
1. impregnate, combine, or supply with oxygen; "oxygenate blood"
(synonym) oxygenize, oxygenise, aerate
(hypernym) process, treat
(derivation) oxygen, O, atomic number 8

(v. t.)
To unite, or cause to combine, with oxygen; to treat with oxygen; to oxidize; as, oxygenated water (hydrogen dioxide).
  

A substance which, when added to gasoline, increases the amount of oxygen in that gasoline blend. Includes fuel ethanol, methanol, and methyl tertiary butyl ether (MTBE). (DOE6)