Source:http://linkedlifedata.com/resource/umls/id/C0030847
MSH: The state of the PENIS when the erectile tissue becomes filled or swollen (tumid) with BLOOD and causes the penis to become rigid and elevated. It is a complex process involving CENTRAL NERVOUS SYSTEM; PERIPHERAL NERVOUS SYSTEMS; HORMONES; SMOOTH MUSCLES; and vascular functions.,CSP: physiological response of penile erectile tissue engorging with blood due to male sexual arousal.,GO: The hardening, enlarging and rising of the penis which often occurs in the sexually aroused male and enables sexual intercourse. Achieved by increased inflow of blood into the vessels of erectile tissue, and decreased outflow. [GOC:jl, Wikipedia:Penile_erection],NCI: In medicine, the swelling of the penis with blood, causing it to become firm.,NCI: The hardening, enlarging and rising of the penis which often occurs in the sexually aroused male.