DictionaryterminatorSomething that ends or stops
noun

terminator

TER-muh-nay-ter/tˈɝmʌnˌeɪtɝ/

Something that brings about or marks an end.

Earth's terminator marks the curved boundary between daylight and darkness.

An isolated view of Earth with a clear curved boundary between its sunlit and nighttime halves: the terminator marks where daylight ends.
Etymology

The pieces express someone who sets an end or boundary. This accounts for both a boundary such as the line between planetary light and darkness and, more generally, a person or thing that ends something.

In context

NASA Night Sky Network15:15
when you see that line between day and night you're seeing the terminator
Global Moon Party - Kickoff International Observe the Moon Night

More examples

  • The program treats a blank line as a record terminator.
  • The cable needs a terminator at its far end.
  • This DNA sequence functions as a terminator, stopping transcription.

Forms

terminator · terminators

terminate verb — To bring something to an end.

termination noun — The act of ending or stopping something.

Similar words

delimiter
A delimiter separates units; a terminator specifically ends one.
stopper
A stopper blocks or halts something rather than marking its end.