test A doorway, entrance, or gate, especially one that is large and imposing.
An entrance or a means of entrance.
the local library, a portal of knowledge.
The portal vein.
A website considered as an entry point to other websites, often by being or providing access to a search engine.
adjective
Of or relating to the portal vein or the portal system.
Of or relating to a point of entrance to an organ, especially the transverse fissure of the liver, through which the blood vessels enter.
From The American Heritage® Dictionary of the English Language, 5th Edition. More at Wordnik