'erratically-constructed' originates from the combination of 'erratic' and 'constructed'. 'Erratic' comes from Latin 'erraticus', meaning 'wandering', and 'constructed' is derived from Latin 'constructus', meaning 'to build'.

'Erraticus' transformed into the Old French 'erratique', and eventually became the modern English word 'erratic'. 'Constructus' evolved into the Old French 'construire', leading to the modern English 'construct'.

Initially, 'erratic' meant 'wandering', but over time it evolved to mean 'unpredictable'. 'Construct' has largely retained its original meaning of 'to build'.