brass 
/ˈbræs, Brit ˈbrɑ:s/ noun
plural brass·es /ˈbræs, Brit ˈbrɑ:s/ noun 1 [noncount] : a yellow metal that is made by combining copper and zinc
▪ a candlestick made of brass — often used before another noun ▪ a brass candlestick 2 : musical instruments (such as trumpets, trombones, and tubas) that are made of brass [noncount] ▪ The whole orchestra—the strings, percussion, woodwinds, and brass—began to play. [plural] ▪ The brasses began to play. — often used before another noun ▪ He's one of the best brass players in the orchestra. ▪ a brass instrument ▪ the orchestra's brass section [=the group of musicians in an orchestra who play brass instruments] — see also brass band 3 [noncount] : bright metal objects made of brass
▪ polishing the brass and the silver 4 [noncount] chiefly US, informal : the people in the highest positions in an organization (such as the military or a business)
▪ Navy brass [=top brass] met earlier today. — often used with the ▪ The brass met earlier today. ◊Brass is used with both plural and singular verbs in this sense.
▪ The company brass have/has decided that no action is necessary at this time.
▪ a candlestick made of brass — often used before another noun ▪ a brass candlestick
▪ polishing the brass and the silver
▪ Navy brass [=top brass] met earlier today. — often used with the ▪ The brass met earlier today. ◊Brass is used with both plural and singular verbs in this sense.
▪ The company brass have/has decided that no action is necessary at this time.
(as) bold as brass — see 1bold
get down to brass tacks
informal : to start to discuss or consider the most important details or facts about something
▪ We finally got down to brass tacks and decided to work out a schedule for the project.
▪ We finally got down to brass tacks and decided to work out a schedule for the project.
