Pronunciation: (ob'strOO-unt),[key] —adj. 1. Med.(of a substance) producing an obstruction.
2. Phonet.(of a speech sound) characterized by stoppage or obstruction of the flow of air from the lungs. Cf. sonorant.
—n. 1. Med.a medicine that closes the natural passages of the body.
2. Phonet.an obstruent speech sound; a stop, fricative, or affricate. Cf. sonorant (def. 2).