- the line dividing the illuminated and dark part of the moon or a planet
WordReference Random House Unabridged Dictionary of American English © 2026
ter•mi•na•tor
(tûr′mə nā′tər),USA pronunciation n.
- a person or thing that terminates.
- Astronomythe dividing line between the illuminated and the unilluminated part of a satellite or planet, esp. the moon.
- Late Latin terminātor, equivalent. to terminā(re) to terminate + -tor -tor
- 1760–70
Collins Concise English Dictionary © HarperCollins Publishers::
terminator /ˈtɜːmɪˌneɪtə/ n
'terminator' also found in these entries (note: many are not synonyms or translations):