a. Pertaining to a sort. [ Obs. ] Locke. [ 1913 Webster ]

n. [ OF. portal, F. portail, LL. portale, fr. L. porta a gate. See Port a gate. ] 1. A door or gate; hence, a way of entrance or exit, especially one that is grand and imposing. [ 1913 Webster ]

Thick with sparkling orient gems
The portal shone. Milton. [ 1913 Webster ]

From out the fiery portal of the east. Shak. [ 1913 Webster ]

2. (Arch.) (a) The lesser gate, where there are two of different dimensions. (b) Formerly, a small square corner in a room separated from the rest of the apartment by wainscoting, forming a short passage to another apartment. (c) By analogy with the French portail, used by recent writers for the whole architectural composition which surrounds and includes the doorways and porches of a church. [ 1913 Webster ]

3. (Bridge Building) The space, at one end, between opposite trusses when these are terminated by inclined braces. [ 1913 Webster ]

4. A prayer book or breviary; a portass. [ Obs. ] [ 1913 Webster ]

Portal bracing (Bridge Building), a combination of struts and ties which lie in the plane of the inclined braces at a portal, serving to transfer wind pressure from the upper parts of the trusses to an abutment or pier of the bridge. [ 1913 Webster ]

a. (Anat.) Of or pertaining to a porta, especially the porta of the liver; as, the portal vein, which enters the liver at the porta, and divides into capillaries after the manner of an artery. [ 1913 Webster ]

☞ Portal is applied to other veins which break up into capillaries; as, the renal portal veins in the frog. [ 1913 Webster ]