ˈkōdə(r) noun
( -s )
1. : one that codes: as
a. : a device for putting information into a form (as on the perforated tape fed into an automatic telegraph keyer) that facilitates its transmission in code over a communication circuit
b. : one that translates information or instructions into the code of an automatic computer
2. : any of a number of especially electronic devices that translate one set of impulses into another set often of a different kind: as
a. : a device to change or modulate an electric current (as on a track) so that it will operate corresponding controls on a car or other apparatus
b. : a telephone relay device by which a given set of signals (as a dialed telephone number) actuates a selective set of electronic processes
c. : an electronic device by which a number of single-pole single-throw switches can actuate a number of parallel, overlapping, or interrelated circuits
d. : an electronic device used in airplanes for sending coded identification signals
e. : a unit in a radar receiver that translates a simple impulse from a receiver into several impulses