pickdead letter . dead letter {n. phr.} An undeliverable letter that ends up in a special office holding such letters. There is a dead letter office in most major cities. Categories: add yours noun Source: A Dictionary of American Idioms 'dead letter' on video DEAD LETTER CIRCUS - Big Dead Letter Circus - The Burning Number [Official Video] DEAD LETTER CIRCUS - Disconnect and Apply Dead Letter Circus - Silence sort: relevance, mode: exact match, q: "dead letter", maxResults: 4, videoEmbeddable: true, videoSyndicated: true, safeSearch: strict, type: video Subscribe to: American IdiomsEnglish Slang Add my comment