a borough of Allegheny county, Pennsylvania, U.S.A., 6 M. S.W. of Pittsburg. Pop. (1900) 7330, of whom 1816 were foreign-born. It is served by the Pittsburg, Cincinnati, Chicago & St Louis, the Pittsburg, Chartiers & Youghiogheny, and the Wabash Pittsburg Terminal railways, and the Pittsburg street railway. Carnegie is situated in the beautiful valley of Chartiers Creek, and is in one of the coal and natural gas districts of the state. In the borough are a Carnegie library and St Paul's orphan asylum. Among the borough's manufactures are steel, lead, glass, ploughs and enameland tin-ware. There are alkaline and lithia mineral springs here. In 1894 Carnegie, named in honour of Andrew Carnegie, was formed by the union of the boroughs Chartiers and Mansfield.