Commonly-Used American Slang: An alphabetical list of words and expressions, set out as a quiz with hidden answers.
English Idioms and Slang: Alphabetic dictionary of English colloquial words and slang
Sayings Explained: Searchable database of well-known sayings, phrases, and slang, along with definitions and origins.
The Dictionary of Informal, Slang and Idiomatic Phrases: Definitions for all the common expressions used in everyday English speech, with examples of sentences using them.
The Grammar of Slang: Article analyzes the grammar behind contemporary slang. Includes the various uses for 'like', 'stuff', 'whatever', and 'so'.
Twists, Slugs and Roscoes: A Glossary of Hardboiled Slang: Definitions of the lingo used in the crime fiction and movies of the '30's and '40's.