Peerages in the United Kingdom

A peerage is a form of crown distinction, with peerages in the United Kingdom comprising both hereditary and lifetime titled appointments of various ranks, which form both a constituent part of the legislative process and the British honours system within the framework of the Constitution of the United Kingdom. The term peerage can be used both collectively, to refer to this entire body of titled nobility (or a subdivision thereof), and individually, to refer to a specific title (modern English language-style using an initial capital in the latter case but not the former).

Source: Wikipedia — Peerages in the United Kingdom (CC BY-SA 4.0)