Etimolojik olarak, ἄπειρος(apeiron) genellikle πέρας ya da πεῖραρ kelimesinden türemiştir ve her ikisi de sınır, limit ve son anlamına gelmektedir.
Etymologically, ἄπειρος is usually derived either from the word πέρας, or from πεῖραρ, both in the sense of ‘limit’, ‘boundary’ or ‘end’.