The Collaborative International Dictionary of English v.0.48:
Cardiac \Car"di*ac\, a. [L. cardiacus, Gr. ?, fr. ? heart: cf. F. cardiaque.] 1. (Anat.) Pertaining to, resembling, or hear the heart; as, the cardiac arteries; the cardiac, or left, end of the stomach. [1913 Webster] 2. (Med.) Exciting action in the heart, through the medium of the stomach; cordial; stimulant. [1913 Webster] Cardiac passion (Med.) cardialgia; heartburn. [Archaic] Cardiac wheel. (Mach.) See Heart wheel. [1913 Webster]