What does the brass mean, exactly, in military context

In books by many different authors I encountered phrases like this: He curses the brass for not caring whether he lives or dies. From context, it seemed to me that it meant high-rank officers

Top Brass

What the U.S. Military Really Thinks About Biden

What is meant by 'military brass' in a military context? - Quora

Russian general says top military brass betrayed soldiers fighting in Ukraine

A tip of the hat: The evolution of headwear badges of the U.S. Military - Military Trader/Vehicles

Armed force, Definition, Examples, & History

Olds Military Trumpet — Robb Stewart Brass Instruments

The History Of Boonie Hats In The U.S. Military

Regiments of the Civil War American Battlefield Trust