In the same vein as "man overboard," a literal interpretation of the phrase refers to a drag queen who has fallen to the ground. Its meaning has been expanded to describe any person who 1. trips or loses footing, or 2. is generally a hot mess.
Guy #1: "So I'm licking his-" *trips over rock*
Onlooker: "Tranny down!"
or
Guy #1: "Did you see Ryan at the bar last night?"
Guy #2: "Ooh. Tranny down, girl."
by Joshua H. September 9, 2005
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It is when a Tranny bitch gets shot and all the other tranny bitches scream "Tranny Down" and then they run like bitches.
***Gun fire****

Tranny1 "Oh shit, I just got shot!"

Tranny2 "Tranny Down! Fuck this! Run Bitches Run."
by Dj and Glenn August 6, 2006
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