'steadily-composed' originates from the combination of 'steady' and 'composed', where 'steady' meant 'firmly fixed' and 'composed' meant 'calm and self-controlled'.

'steady' changed from Old English 'stede' meaning 'place' and 'composed' from Latin 'componere' meaning 'to put together'.

Initially, 'steadily-composed' meant 'firmly calm', but over time it evolved into its current meaning of 'calm and consistent in demeanor'.