nitric oxide

noun

Definition of nitric oxide

: a colorless poisonous gas NO formed by oxidation of nitrogen or ammonia that is present in the atmosphere and also in mammals where it is synthesized from arginine and oxygen and acts as a vasodilator and as a mediator of cell-to-cell communication (as between nerve cells) — compare nitrous oxide

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First Known Use of nitric oxide

1789

in the meaning defined above

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Medical Dictionary

nitric oxide

noun

medical Definition of nitric oxide

: a poisonous colorless gas NO that occurs as a common air pollutant formed by the oxidation of atmospheric nitrogen and that is also formed by the oxidation of arginine in the mammalian body where it acts as a mediator of intracellular and intercellular communication regulating numerous biological processes (as vasodilation and neurotransmission)

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