stovepipe
verb
stovepiped; stovepiping; stovepipes
: to transmit (information) to a higher level in an organization through an isolated and narrow channel of communication
This [Pentagon policy] office, which circumvented the usual procedures of vetting and transparency, stovepiped many of its findings to the highest-ranking officials.—
Seymour M. Hersh
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Merriam-Webster unabridged



