Fuel efficiency is an important factor to consider when choosing a vehicle, as it can save you money on gas and reduce the vehicle's carbon footprint. There are several synonyms for the term "fuel-efficient" that can be used to describe a car, such as energy-efficient, eco-friendly, low-emission, and gas-saving. Other possible synonyms include mileage-smart, fuel-thrifty, environment-friendly, and green-driven. No matter what term you choose to use, the common thread is that these vehicles are designed to optimize fuel usage and minimize waste. In today's environmentally conscious world, finding a fuel-efficient vehicle is an important step towards reducing our impact on the planet.