- Urban Dictionary
- A searchable archive of contemporary American slang, listed in alphabetical order. Allows its users to create definitions for slang words and phrases and submit them for publication. Includes a "Word of the Day" section, chat features and live minute-by-minute site update logs. - A Dictionary of Old Hobo Slang - A searchable compilation of slang used by vagrants and migratory workers, listed in alphabetical order.
- A Dictionary of Slang - English slang and colloquialisms currently used in the United Kingdom. Includes definitions, a part of speech listing and an example sentence for each term.
- Businessballs.com - Cockney Rhyming Slang - Origins, derivations and dictionary translations of the slang used by inhabitants of the East End district of London, England.
- Carleton County Colloquialisms - Dictionary of the colloquial language of Carleton County, New Brunswick, Canada and Aroostook County, Maine, USA. Audio clips accompany each entry.
- ChatRef.com - Definitions of acronyms, abbreviations, and emoticons used in online chat and text messaging.
- Double-Tongued Dictionary - A growing dictionary of words from the fringes of English, including jargon, slang, and loan words. Browsable by category or searchable by letter. Includes analysis of new words, and modern connotations of words with old denotations.
- idioMeanings - Online English idiom dictionary.
- London Slang - Online word and phrase dictionary of cockney rhyming slang. Also includes examples of film slang.
- PseudoDictionary - Covers slang, made up words, "webspeak", colloquialisms and accepts contributions for new entries.
- Slang Search - Definitions of common words in English-language slang, organized by subject area.
- Slang-Dictionary.org - A searchable archive of colloquial English used in American society, the UK in the 18th and 19th centuries, Australia, hip-hop culture, modern-day London, and the American underworld.
- SlangSite.com - A dictionary of slang, webspeak, made up words, and colloquialisms. Submissions welcome.
- Southern Slang Dictionary - Colloquial American words and expressions originating specifically from Arkansas. Notes part of speech and includes example sentences. Sorted alphabetically.
- The Online Slang Dictionary - A global dictionary of English slang compiled from user submissions. Includes a slang thesaurus and word lists browsable by letter.
- The Septic's Companion - A dictionary of British slang, viewable alphabetically or by category.
- Twittonary Dictionary - A dictionary of Twitter words submitted by tweeters.
