Erectile tissue
Erectile tissue is tissue in the body with numerous vascular spaces, or cavernous tissue, that may become engorged with blood. However, tissue that is devoid of or otherwise lacking erectile tissue may also be described as engorging with blood, often with regard to sexual arousal.
In sex organs
[Image:Gray1155 a.png|thumb|right|200px|Cross section showing the two corpora cavernosa near the top surface of the penis, and the corpus spongiosum surrounding the urethra near the bottom surface]Image:Clitoral body, [internal anatomy.png|thumb|right|Cross section showing the two corpora cavernosa of the clitoris]
Erectile tissue exists in external genitals such as the corpora cavernosa of the penis and their homologs in the clitoris, also called the corpora cavernosa. During penile or clitoral erection, the corpora cavernosa will become engorged with arterial blood, a process called tumescence. This may result from any of various physiological stimuli which can be internal or external. This process of stimulation, due to internal or external stimuli, is also known as sexual arousal. The corpus spongiosum is a single tubular structure located just below the corpora cavernosa in males. This may also become slightly engorged with blood, but less so than the corpora cavernosa.