'non-mitochondrial' originates from Modern English, specifically the prefix 'non-' and the adjective 'mitochondrial', where 'non-' meant 'not' and 'mitochondrial' related to 'mitochondrion', the cell organelle.

'mitochondrion' comes from Greek 'mitos' ("thread") + 'chondrion' ("small granule"); the scientific term 'mitochondrion' was coined in the late 19th century (often credited to Carl Benda, 1898), 'mitochondrial' is the adjectival form, and Modern English negative prefix 'non-' was attached to form 'non-mitochondrial'.

Initially the Greek-rooted term described thread- or granule-like structures, then came to denote the organelle responsible for cellular energy production; 'non-mitochondrial' developed to mean 'not associated with mitochondria'.