cor

Cor, cordis, n., third declension. Neuter, so cor serves as both nominative and accusative, the plural is corda, and the genitive plural cordium shows the i-stem. The single-syllable nominative hides the d of the stem.

For the Romans the heart was the seat of intelligence at least as much as of feeling, so cordatus means shrewd and excors means stupid rather than heartless. The idiom cordi est mihi, "it is at heart to me", is the ordinary way to say that something matters to you, and it takes a dative of the person. In Christian Latin the emotional sense dominates and gives the Sacred Heart, sacrum cor. English inherited a large family through French: core, courage, cordial, concord, discord, record and, from recordor, "call back to mind", the whole business of recording.