OS X: disable CMD-H or "Hide App" command?
You might use a private.xml like this with Karabiner (formerly KeyRemap4MacBook):

&lt;?xml version="1.0"?&gt;
&lt;root&gt;
  &lt;item&gt;
    &lt;name&gt;test&lt;/name&gt;
    &lt;identifier&gt;test&lt;/identifier&gt;
    &lt;autogen&gt;__KeyToKey__ KeyCode::H, VK_COMMAND | ModifierFlag::NONE, KeyCode::VK_NONE&lt;/autogen&gt;
  &lt;/item&gt;
&lt;/root&gt;