noun
also rous' sarcoma or rous's sarcoma ˈrau̇s(ə̇z)-
Usage: usually capitalized R
Etymology: after F. Peyton Rous b 1879 American physician
: a readily transplantable malignant spindle-cell sarcoma of chickens that is transmissible by cell-free filtrate and so is regarded as due to a specific carcinogenic virus