Delete user metadata per site or network-wide.
User options are just like user metadata except that they have support for blog-specific options when using multisite. If the $global parameter is false, which it is by default, it will prepend the WordPress table prefix to the option name. This will delete the site-specific metadata for the user, rather than the network-wide metadata.
<?php delete_user_option( $user_id, $option_name, $global ); ?>
delete_user_option() is located in