Meaning of 'portal'

noun

a grand and imposing entrance (often extended metaphorically)

Example: "the portals of the cathedral"

noun

a short vein that carries blood into the liver

Synonyms: portal vein hepatic portal vein

noun

a site that the owner positions as an entrance to other sites on the internet

Example: "a portal typically has search engines and free email and chat rooms etc."

Synonyms: portal site