Wordnet 3.0
NOUN (1)
1. 
 (anatomy) the base of a hollow organ or that part of the organ farthest from its opening; 
- Example: "the uterine fundus"- Example: "the fundus of the stomach"
The Collaborative International Dictionary of English v.0.48:
Fundus \Fun"dus\ (f[u^]n"d[u^]s), n. [L., bottom.] (Anat.)
   The bottom or base of any hollow organ; as, the fundus of the
   bladder; the fundus of the eye; the fundus of the uterus.
   [1913 Webster]
WordNet (r) 3.0 (2006):
fundus
    n 1: (anatomy) the base of a hollow organ or that part of the
         organ farthest from its opening; "the uterine fundus"; "the
         fundus of the stomach"
Bouvier's Law Dictionary, Revised 6th Ed (1856):
FUNDUS, civil raw. Any portion of land whatever, without considering the use
or employ to which it is applied.