(n) An anacronym for "Multi User Character Kingdom" or other variations. Refers to a complex, often theme-oriented chatroom environment, similar to a MMORPG only text-based rather graphical and usually intended for online socialization. MUCKs are accessable either through telnet or specially designed programs known as "clients" (i.e. SimpleMU* or MUSHClient) and generally possess some degree of roleplaying.
1. She spends more time on the MUCK than she does watching TV.
2. Dave downloaded a client and registered for a character on the MUCK.