noun (plural -cies) Date: 1633 the quality or degree of being efficient, 2. efficient operation, b. effective operation as measured by a comparison of production with cost (as in energy, time, and money), the ratio of the useful energy delivered by a dynamic system to the energy supplied to it, ~ apartment
EFFICIENCY
Meaning of EFFICIENCY in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012