'atelo' originates from Greek, specifically the word 'atelēs', where 'a-' meant 'not' and 'telēs' meant 'complete'.

'atelo' was formed from ancient Greek 'atelēs' and entered New Latin/scientific vocabulary as the combining form 'atelo-' used in medical and biological coinages, then passed into modern English technical usage.

Initially it meant 'not complete' or 'imperfect'; this basic sense has been retained in modern scientific and medical usage.