accelerometer
n. countable C1 Advanced US //ækˌsɛɫɝˈɑmətɝ// UK //ɐksˌɛləɹˈɒmɪtɐ// ac·celerom·e·ter
n. a small electronic device that measures how fast something is speeding up or slowing down. You find these in phones, cars, and even fitness trackers to detect movement.
n. an electronic sensor that measures proper acceleration, which is the acceleration experienced by the device itself. It is used to detect changes in velocity, orientation, and shock.
The phone uses an accelerometer to know when you turn it sideways.
Modern cars are equipped with an accelerometer to trigger the airbags instantly during a sudden stop.
By integrating data from a high-precision accelerometer with a gyroscope, the navigation system can maintain its orientation even when the satellite signal is lost.
From accelerate + -o- + -meter.