The word terminator is from Latin and means roughly the finisher.
- In astronomy, the terminator is the line between the day side and the night side of a planetary body. Examination of the terminator can yield information about the surface of the body; for example, a fuzzy terminator indicates the presence of an atmosphere. On Earth, sunrise and sunset are the result of passing through the terminator each day.
- In genetics, a terminator marks the end of a gene on the DNA for transcription.
- The Terminator is an American motion picture involving a cyborg that has been sent back through time to "terminate" or kill a woman whose life will have importance in the future.
- In electronics, a resistor at the end of a transmission line or daisy chain bus (such as in SCSI), designed to match impedance and hence minimize reflections of the signal.