There are several definitions for MDIH.
1. MDIH is an acronym of the phrase/club "My dick is huge".
2. An exclusive and private club that prides itself in their incredibly above average sized male genitalia. The club's sole purpose is to bring humiliation to males whose reproductive organs are of small-scale. MDIH members refer to these people as "Asian".
3. A Halo 3 clan that kicks ass and ridicules the Asian sized penises of their opponents.
MDIH OWNS YOU