Laënnec, René Théophile Hyacinthe (rənāˈ tāôfēlˈ yäsaNtˈ läānĕkˈ) [key], 1781–1826, French physician. While connected with the Necker Hospital in Paris he invented the stethoscope, which he described, together with the symptoms he had noted through its use, in his classic book De l'auscultation médiate (2 vol. 1819; tr. 1821). His method of auscultation for detecting diseases of the chest, together with the procedure of percussion developed by Leopold Auenbrugger, form the basis of the modern diagnostic technique.
See study by R. Kervran (1960).