Erection

Erection
Three columns o erectile tissue mak up maist o the volume o the penis.
An erect human penis.
Anatomical terminology [eedit on Wikidata]

An erection (clinically: penile erection or penile tumescence) is a pheesiological phenomenon in which the penis acomes firmer, engorged an enlairged. Penile erection is the result o a complex interaction o psychological, neural, vascular an endocrine factors, an is often associatit wi sexual aroosal or sexual attraction, althou erections can an aa be spontaneous.