'reactively-placed' originates from the combination of 'reactive' and 'placed', where 'reactive' comes from Latin 'reactivus', meaning 'to act in response', and 'placed' from Old French 'placer', meaning 'to arrange'.

'reactive' changed from the Latin word 'reactivus' and 'placed' from the Old French word 'placer', eventually forming the modern English term 'reactively-placed'.

Initially, 'reactive' meant 'to act in response', and 'placed' meant 'to arrange'. Together, they evolved to mean 'positioned in response to a stimulus'.