'non-metamorphic' originates from the prefix 'non-' meaning 'not' and 'metamorphic' from Greek 'metamorphosis', where 'meta-' meant 'change' and 'morphe' meant 'form'.

'metamorphosis' transformed into the English word 'metamorphic', and with the addition of 'non-', it became 'non-metamorphic'.

Initially, 'metamorphic' meant 'change in form', and 'non-metamorphic' has retained the meaning of 'not changing form'.