'externally-generated' originates from the combination of 'external' and 'generate', where 'external' comes from Latin 'externus' meaning 'outside', and 'generate' from Latin 'generare' meaning 'to produce'.

'Externus' transformed into the Old French word 'externe', and 'generare' into the Old French 'generer', eventually forming the modern English 'external' and 'generate'.

Initially, 'external' meant 'outside' and 'generate' meant 'to produce', and together they evolved to mean 'produced by external factors'.