Etymology tree Proto-Indo-European *h₂ep Proto-Indo-European *-o Proto-Indo-European *h₂epó Proto-Hellenic *apó Ancient Greek ᾰ̓πό (ăpó) Ancient Greek ᾰ̓πο- (ăpo-)bor. English apo- Proto-Indo-European *ḱent-der. Ancient Greek κέντρον (kéntron)der. Latin centrumder. Middle French centrebor. Middle English center English center English apocenter From apo- + center.