terminator.

1. The dividing line between the illuminated and dark portions of a planetary or similar body.

2. A person or thing that brings an activity or process to an end.

3. A character or sequence that marks the end of a data item or instruction.

Use it for

Words that belong together

• lunar terminator
• cross the terminator

On the page

The ship crossed the lunar terminator into a darkness without haze.

Along the terminator, mountain shadows stretched across the crater floor.

Usage notes

Primary category: sci-fi. Forms: Singular terminator; plural terminators. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings.