'energy-reflecting' originates from Modern English, combining the noun 'energy' and the present participle 'reflecting'.

'energy' originates from Greek, specifically the word 'energeia', which passed into Latin and then Old French before becoming Middle and Modern English 'energy'. 'reflect' comes from Latin 'reflectere' (re- 'back' + flectere 'to bend'), entered English via Old French/Medieval Latin and became 'reflect' in Middle English; the compound form is a modern English creation combining these elements.

Initially, 'energy' and 'reflect' had their separate technical meanings ('energeia' as 'activity, operation' and 'reflectere' as 'to bend back'); over time they combined in Modern English to form descriptive compounds like 'energy-reflecting', whose current meaning is 'causing energy to be reflected'.