Dictionary.net

1. The bottom or lowest part of a sac or hollow organ, that farthest removed from the opening. 2. The cardiac end of the stomach, the main reservoir for the reception of food and its peptic digestion, partly shut off, during digestion, from the antrum, or pyloric end, by the prepyloric sphincter.

Visceral base.

The base of an organ, as of stomach, etc..

The base of any organ which ends in a neck, or has an external aperture; as the Fundus vesicae, F. uteri, &c. Also, the Vulva.

The base or part remotest from the mouth of a hollow organ.