a member of the lowest grade of nobility.

(in Britain)

a feudal vassal holding his lands under a direct grant from the king.

a direct descendant of such a vassal or his equal in the nobility.

a member of the House of Lords.

an important financier or industrialist, esp. one with great power in a particular area

an oil baron.

a cut of mutton or lamb comprising the two loins, or saddle, and the hind legs.

noun

peer , lord , aristocrat , capitalist , king , magnate , mogul , noble , tycoon