letterlet·ter /ˈletə-ər/ noun [countableC]1a written or printed message that is usually put in an envelope and sent by mailPlease sign the letter and mail it back within two weeks.
→ allocation letter → appointment letter → comfort letter → covering letter → engagement letter → form letter2any of the signs in writing or printing that represent a speech soundthe letter ‘A’
4LAW the letter of the law the exact words of a law or agreement rather than the intended or general meaningan administrator with a rigid adherence to the letter of the law