'externally-caused' originates from the combination of 'external' and 'cause', where 'external' comes from Latin 'externus' meaning 'outside' and 'cause' from Latin 'causa' meaning 'reason'.

'Externus' transformed into the Old French word 'externe', and eventually became the modern English word 'external'. 'Causa' evolved into the Old French 'cause', leading to the modern English 'cause'.

Initially, 'external' meant 'outside', and 'cause' meant 'reason'. The combination 'externally-caused' retains the meaning of being caused by outside factors.