'reduced-calorie' originates from the combination of 'reduce' and 'calorie', where 'reduce' means 'to make smaller or less in amount' and 'calorie' refers to a unit of energy.

The term 'reduced-calorie' evolved from the increasing awareness of dietary needs and the demand for healthier food options.

Initially, it meant 'lower in energy content', and this meaning has largely remained the same in modern usage.