No more writeups are being accepted for this node. This node has been locked because it is (almost) always an acronym for something else.
If you create a node that MD stands in for, and the full name does not already appear in the "See Also:" list above, please contact an editor to add it to the list.If you would like to add a writeup that MD directly pertains to, please place it in your E2 Scratch Pad and contact an editor to unlock the node for you. If you feel you have something to add to this node, post it on your Scratch Pad and contact an editor.
