People who talk on the TV or radio about sports.
Sportscasters tell people what is happening in sports, and they usually know a lot about sports.
Examples:
The sportscasters said the home team won the game.
I like to listen to the sportscasters on the radio.
The sportscasters are talking about the basketball game.
The sportscasters make the game more fun to watch.
The sportscasters know everything about sports.
The sportscasters are my favorite part of watching sports on TV.