linesman
nounUK /ˈlaɪnzmən/
US /ˈlaɪnzmən/
A linesman is a person who helps the referee make sure the game is played fairly.
The linesman raised his flag to show the ball had gone out of play.
RELATED WORDS
OTHER MEANINGS
2. A person whose job is to repair and take care of telephone or electrical power lines.
The linesman climbed the pole to fix the broken wire.
3. A worker who lays or repairs railway tracks.
The linesman checked the rails before the train arrived.
4. In tennis, an official who judges whether a ball lands inside or outside the lines.
The linesman called the shot out.