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Third-Party Intermediary (or Intermediaries)

TPI stands for a lot of different things. I'm just giving one of the definitions here, which is used in certain military/ government/ police situations, also in the worlds of business/ finance.
The setting for my example is a hostage situation (if you've watched the first episode of "Flashpoint" you'll recognize this).... One lone hostage taker has a gun to the head of his hostage. Police presence is all around. A civilian who clearly knows the hostage taker is seeking to intervene.

Police 1 to Police 2: "Hold fire, we have a possible TPI here."
by 1cor13pursuer November 08, 2011
tuned port injection
85-92 camaro run tpi
by toyota dave January 18, 2011