'vaguely-decided' originates from the combination of 'vague' and 'decide', where 'vague' comes from Latin 'vagus' meaning 'wandering' and 'decide' from Latin 'decidere' meaning 'to cut off'.

'vague' changed from the Old French word 'vague' and 'decide' from the Old French 'decider', eventually forming the modern English term 'vaguely-decided'.

Initially, 'vague' meant 'wandering or uncertain', and 'decide' meant 'to cut off or determine'. Together, they evolved to mean 'not clearly determined'.