'metathetic' originates from Greek, specifically the word 'metathesis', where 'meta-' meant 'after' or 'beyond' and the root from 'tithenai' meant 'to place'.

'metathesis' (Greek) entered scientific and linguistic usage in Latin and then English; the adjective 'metathetic' was formed in Modern English from this Greek-derived noun.

Initially it referred to the act or process of 'placing after' or transposition; over time it came to describe items (sounds, letters, morphemes) that have been transposed or the property of having undergone transposition.