'energy-storing' originates from the combination of 'energy' and 'storing', where 'energy' comes from Greek 'energeia' meaning 'activity' and 'storing' from Old English 'stōrian' meaning 'to store'.

'energy-storing' evolved from the concept of 'energy' and 'store', which were used separately in Middle English and later combined in modern English.

Initially, it referred to the act of storing any form of energy, and this meaning has largely remained the same in modern usage.