The /mute command allows you to prevent another player from talking to you in any way, although they will still be able to hear you and other things around them. A player that you have muted will have a "No" sign (a red circle with a line through it) on their pirate's head. A list of players you have muted is kept in the options menu of the game client. The pirate muted will not be informed that they have been muted by another person. You will not be notified if a pirate on your mute list wishes to enter your house. If a muted pirate issues a challenge, trade request, hearty invite or job invite to you, it is automatically declined.
If you mute someone and you try and message that user, you will receive a message saying 'Ye can't tell to a person that ye've muted.' If that user tries to message you, they will receive no message telling them they have been muted.
The list of muted pirates is stored in the client. Muting a pirate mutes that pirate for all of your alts when playing on that computer. If you play from more than one computer, the mute list is not shared between them.
/mute <pirate name>
Prior to the 2005-06-01 release, players could mute the pirate that they were playing as at the time. However, they can still mute one of their own pirates with an alt. If a player attempts to mute the pirate that they are playing at the time a message comes up on screen that says: "Talking to oneself is a sign of impending insanity," (The same message comes up if one tries to send a /tell to oneself.)
The syntax of the mute command is such that you may mute anything you wish; for example muting 78jf7# will prompt the response, You have muted '78jf7#'.. However since this pirate name cannot exist, effecting this user-line input will have no effect other than adding a line of clutter to your list of muted pirates.