Definition of the word top gear

The phrase "top gear" originated in the early 20th century when referring to trains. It described a state where a train's locomotive was running at its maximum speed, offering optimal performance. However, the term was also co-opted by the automotive industry, particularly in the 1930s, to describe a car's highest gear. The idea was that in this gear, the engine was running at peak performance, delivering maximum power to the wheels and optimal fuel efficiency. This usage of "top gear" continues today, not just in the automotive industry, but also in the context of motorcycles, bicycles, trucks, and other vehicles. It remains a way to describe an optimal gear ratio or speed for optimal efficiency or performance. Outside of the automotive world, "top gear" has also been used in nonsensical contexts, like during political campaigns where a candidate may be described as being "in top gear" when performing well. Regardless of the context, "top gear" remains a popular phrase because it offers a clear and straightforward way to indicate optimal operation, efficiency, and performance.