Formerly, an armor bearer, as of a knight, an esquire who bore his shield and rendered other services. In later use, one next in degree to a knight, and entitled to armorial bearings. The term is now superseded by esquire.

Someone who bears or is entitled to bear arms

An armiger is someone entitled to bear heraldic arms, as opposed to an esquire, carried someone else's arms..

a person who has bee awarded arms by the Crown Heraldry uses a limited set of clear, bold "tinctures"

a person who has been awarded arms by the Crown

A person who has an award of arms or higher, q. v. Any person may be addressed as "milord" or "milady," but only an armiger is properly addressed as "Lord X" or "Lady Y."