mph stands for miles per hour. It's a unit of speed, specifically how many miles an object travels in one hour.

While it's not exclusively a "science" term, it's often used in scientific contexts when discussing:

* Motion: Describing the speed of objects, like cars, airplanes, or even the wind.

* Physics: Calculating velocity and acceleration, which often involve units of speed.

* Engineering: Designing systems that move or are affected by motion.

Remember, the metric equivalent of mph is kilometers per hour (km/h).