send in
verb1
Historical To give (one's name), present (one's card) when making a social call.
2
To cause (something) to be delivered, especially by post/mail.
3
To send (someone) into the thick of things, as
- send in the cavalry
- send in the clowns
› To send (someone) into the thick of things, as:
4
To send (troops) into battle.
5
Ball games, Cricket, Games, Hobbies, Lifestyle, Sports To send (a batsman) onto the field to bat.