'reactively-shaped' originates from the combination of 'reactive' and 'shaped'. 'Reactive' comes from the Latin word 'reactivus', where 're-' meant 'again' and 'activus' meant 'active'. 'Shaped' is derived from the Old English word 'sceapian', meaning 'to form or create'.

'Reactive' evolved from the Latin 'reactivus' through Middle English, while 'shaped' transformed from the Old English 'sceapian' to the modern English 'shaped'.

Initially, 'reactive' meant 'capable of reacting', and 'shaped' meant 'formed'. Together, they evolved to describe something formed in response to stimuli.