To drop or delete a user in MySQL, you can use the `DROP USER` statement followed by the `username` and `host`. Here's the basic syntax:

Where `username` is The username you want to drop and `host` is The host from which the user is allowed to connect.

For example, to drop a user named `olduser` that can connect from any host, you would use the following SQL statement:

After dropping the user, you should also revoke any privileges that were granted to the user.