Customizing the metamodel : Keywords for USRPROPS : HIDE DEFINITION
  
HIDE DEFINITION
Removes the referenced definition type from the New Definition and Open Definition dialogs.
Note Exercise care when hiding definitions, especially if they are used by symbols that you have made active by choices in the Property Configuration dialog (Tools, Customize Method Support). You may find yourself in a situation where you are drawing symbols with no underlying definitions.
Syntax
HIDE DEFINITION <definition name>
Example
HIDE DEFINITION "SQL Server Table"