veloci-, veloc-, velo- +

Be swifter than life.

An instrument used to measure the speed of a fluid or sound.

Any of various early forms of bicycle or tricycle, including some that had pedals attached to the front wheel or were propelled by pushing the feet along the ground; later it applied to a form of railroad vehicle propelled by pedals and even to a railroad handcar (from Latin veloc-, "swift" plus the stem ped-, "foot").

One who rides a velocipede.

A “swift lizard” from Late Cretaceous South America. Named by Argentinian paleontologist José Bonaparte in 1991.

1. The speed at which something moves, happens, or is done.
2. A measure of the rate of change in position of something with respect to time, involving speed and direction.
3. Rapidity or celerity of motion; swiftness, speed.

A stadium that has a banked track for bicycle races.

A device in which the output of a tachogenerator is fed back so as to keep the rotational speed of a shaft proportional to an applied voltage.

An instrument for measuring the speed of air, or of an aircraft through the air.