'customarily-joined' originates from the English word 'customarily,' which comes from the Latin 'consuetudinarius,' meaning 'according to custom,' and 'joined,' from the Latin 'jungere,' meaning 'to join.'

'customarily' evolved from the Old French 'costumier,' and 'joined' from the Old French 'joindre,' eventually forming the modern English term 'customarily-joined.'

Initially, 'customarily' meant 'according to custom,' and 'joined' meant 'to unite,' evolving into the current meaning of 'typically connected.'