Source : Webster's Revised Unabridged Dictionary (1913)

Exocardiac \Ex`o*car"di*ac\, Exocardial \Ex`o*car"di*al\, a.
   [Exo- + Gr. ? heat.] (Anat.)
   Situated or arising outside of the heat; as, exocardial
   murmurs; -- opposed to {endocardiac}.