'preemptively-assembled' originates from the combination of 'preemptive' and 'assemble'. 'Preemptive' comes from Latin 'praeemptivus', meaning 'to buy before', and 'assemble' from Latin 'assimblare', meaning 'to bring together'.

'Preemptive' evolved from Latin 'praeemptivus' through Old French 'preemptif', while 'assemble' evolved from Latin 'assimblare' through Old French 'assembler'.

Initially, 'preemptive' meant 'to buy before others', but it evolved to mean 'acting in advance to prevent something'. 'Assemble' has largely retained its meaning of 'bringing together parts'.