linemarker
nounUK /ˈlaɪnˌmɑːkə/
US /ˈlaɪnˌmɑːrkər/
A linemarker is a tool or person that draws or marks lines.
The referee used a linemarker to draw the boundary on the field.
OTHER MEANINGS
2. A device that marks lines on a road or sports field.
The groundskeeper set the linemarker at the edge of the pitch.
3. A person who marks lines, such as on a railway or construction site.
The linemarker measured the track before the crew began work.
4. A software feature that highlights or marks lines in a document or code editor.
The linemarker showed which lines had changed in the file.