'nontransposable' originates from English by combining the prefix 'non-' (from Latin 'non' meaning 'not') with 'transposable', which ultimately comes from Latin 'transponere', where 'trans-' meant 'across' and 'ponere' meant 'to place'.

'transponere' (Latin) developed into Old French/Medieval Latin forms such as 'transposer' and into Middle English 'transpose', giving the adjective 'transposable'; the modern English word 'nontransposable' was formed by prefixing 'non-' to 'transposable'.

Originally 'transponere' meant 'to place across' or 'to change position'; over time 'transpose' came to mean 'to change order or position', so 'transposable' meant 'able to be transposed' and 'nontransposable' came to mean 'not able to be transposed'.