brass hat

Etymology
From the military brass insignia on a service hat.

Noun

 * 1)  A high-ranking officer.
 * 2) * 1982, Countdown begins for Space Shuttle, The New York Times:
 * "American brass hats make no secret that they regard outer space as a potential theater of military operations," it said.
 * 1) * 2006, Andrew Roth, Obituary: Lord Monro of Langholm, The Guardian:
 * He raised his first storm in January 1967 when, as leader of the "Save the Argylls" campaign, he claimed the brass hats had driven the regiment's commanding officer, Lieutenant Colonel Colin "Mad Mitch" Mitchell, into resignation.
 * 1) * 2011, Andrew Roth, Gaddafi faces endgame as he bribes civilians to fight for him, The Independent:
 * This being Libya, there were conflicting signals yesterday – an army brass hat captured here, a counter-attack by Gaddafi forces there