From Greek 'kardia' (heart) + '-logia' (study) — the same ancient root behind 'heart,' 'courage,' and 'core.'
The branch of medicine dealing with disorders of the heart.
From Greek kardia (καρδία, heart) + -logia (the study of, discourse about). Greek kardia comes from PIE *kerd- (heart) — one of the most perfectly preserved PIE roots across daughter languages. English heart derives from Proto-Germanic *hertan-, itself from *kerd-; Latin cor (heart, as in cordial, courage, accord) likewise; Sanskrit
'Cardiology,' 'heart,' 'courage,' 'core,' 'cordial,' 'accord,' and 'record' all come from PIE *ḱerd- (heart). Cardiology studies the heart. Heart IS the heart. Courage is 'heart-ness.' Core is the 'heart' of something. Cordial means 'from the heart.' Accord is 'heart to heart.' A record originally placed something 'back