a volatile liquid, CHNO, that is inhaled to dilate blood vessels, esp. in angina pectoris
A volatile yellow liquid, C5H11NO2, formerly used in medicine as a vasodilator, but now replaced by other nitrates, such as nitroglycerin. It is used illicitly to induce euphoria and enhance sexual stimulation.
The non-chemical use of the term is always of isoamyl nitrite, the vasodilator and stimulant.