The term ‘apeiron’ signifies that which is ‘apeiras’, ‘without limit’ or ‘without bounds’. This Apeiron apparently lacked all the ‘bounds’ or ‘limits’ that other things were subject to. It was, it seems, unlimited in time and space; it was unlimited in quality in that it displayed no qualities.
This passage provides the foundational classical definition of ‘unlimited’ as Anaximander’s apeiron — a divine, boundless substrate unlimited in time, space, and qualitative determination, from which all differentiated things originate.
, Psychological and Ethical Ideas What Early Greeks Say, 1995thesis