Wordnet 3.0
NOUN (1)
1. 
 the innermost membrane of an organ (especially the inner lining of an artery or vein or lymphatic vessel); 
The Collaborative International Dictionary of English v.0.48:
intima \intima\ n. (Anat.)
   the innermost coat of an organ, such as a blood vessel. It
   usually consists of an endothelial layer of cells, backed by
   connective tissue and elastic tissue.
   [PJC]
WordNet (r) 3.0 (2006):
intima
    n 1: the innermost membrane of an organ (especially the inner
         lining of an artery or vein or lymphatic vessel)