Apsis
An apsis (from Ancient Greek ἁψίς (hapsís) 'arch, vault' (third declension); pl. apsides AP-sih-deez) is the farthest or nearest point in the orbit of a planetary body about its primary body.
From Wikipedia
An apsis (from Ancient Greek ἁψίς (hapsís) 'arch, vault' (third declension); pl. apsides AP-sih-deez) is the farthest or nearest point in the orbit of a planetary body about its primary body.