/ Dictionary / Index P portal system: Meaning and Definition of Find definitions for: por'tal sys"tem Pronunciation: [key] — Anat. Anat. a vascular arrangement in which blood from the capillaries of one organ is transported to the capillaries of another organ by a connecting vein or veins. (loosely) the hepatoportal system. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. portal circulation portal-to-portal pay Related Content Daily Word Quiz: simian Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language