The definition of an IV is an abbreviation for intravenous, a procedure where a needle inserted directly into a vein to deliver liquids to the blood stream.(abbreviation)
An example of an IV is what a nurse would use to give fluids to a severely dehydrated person.
See IV in Webster's New World College Dictionary
noun pl. IVs
Origin: < i(ntra)v(enous)
See IV in American Heritage Dictionary 4
Origin: From i(ntra)v(enous).
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