'Story Teller's Discretion'.

This phrase indicates the Story Teller (or DM, or GM, depending on what game one is playing) decides to make reality shift in a particular way. Often-times done in order to make the story develop in a particular manner.
1. Upon reaching the anti-climactic 'Final Encounter' of a long and drawn out quest for the artifact needed to enter the Bastion of Broken souls (A fragment of the soul totem), Fighter: The human fighter rolled three natural twenties in a row, which resulted in the untimely (one-round-kill) demise of the fallen god.

However, in order to promote the challenge of this encounter, the DM decides to use an STD to allow a centuries old Contingency heal to revive the poor fellow, at full hitpoints, and rather angry at having been slain in such a way. Then a 'true' fight ensued.

2. Thor throwing his famed hammer Mjollnir(Molniya) at a Werewolf in D&D Edition 3.5, and deciding not to remove the 10 damage which would be removed, since the hammer isn't made of silver. This STD though perhaps un-needed (the werewolf would likely die from the modified damage) makes sense, since even though it's not a silver weapon perse; when Thor throws his hammer, he means business, and that 10 damage shouldn't be reduced because it's not made of silver.
by Crispy (LS) December 16, 2005
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A very contagious STD, children.
ughh.... I have an std.... children.
by Inuyashax April 24, 2006
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An Acronym, South Taranaki District
I live in STD
by martzb September 19, 2003
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Guy 1: "Motherfucker I got a lot of STD's today."

Guy 2: "Yeah, you can can go ahead and finish that joint."
by Salami Sandwich In My Pants August 5, 2009
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STD is an acronym for "Seize the Dave!" It can be used as a shortened name for the infamous website seizethedave.com, or to secretly announce that you will be abducting a nearby person named Dave.
There he is, STD before he gets away!
by Rocket Johnny (IGTF member) December 20, 2002
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stands for Super Trendy Don
i got it from tv sex pals
"ok sticky what does STD stand for?"
"it stands for Super Trendy Don"
"sticky u idiot"
by a girl with nothing to do August 24, 2006
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