What's the difference between tach and tachometer?

Tach

Definition:

Example Sentences:

Definition:

(n.) An instrument for measuring the velocity, or indicating changes in the velocity, of a moving body or substance.
(n.) An instrument for measuring the velocity of running water in a river or canal, consisting of a wheel with inclined vanes, which is turned by the current. The rotations of the wheel are recorded by clockwork.
(n.) An instrument for showing at any moment the speed of a revolving shaft, consisting of a delicate revolving conical pendulum which is driven by the shaft, and the action of which by change of speed moves a pointer which indicates the speed on a graduated dial.
(n.) An instrument for measuring the velocity of the blood; a haematachometer.

Example Sentences:

(1) Speed settings were recorded as percentages of the servomechanism's maximum tachometer feedback voltage (10 to 100% Vfb max).
(2) Speed settings were standardized percentages of each machine's maximum tachometer feedback voltage (0 to 100% Vfb max).
(3) Displays of a tachometer and a special timing device are large enough to be clearly visible on the film.
(4) A Grass polygraph and tachometer were used to record the applied pulses and nodal firing rates; simultaneous magnetic tape recordings were obtained and used for data analysis.
(5) This report describes a safe and inexpensive method of modifying a centrifuge lid so that calibration of the machine with a photoelectric tachometer is a simple and safe procedure.