ManyThings.org - ManyThings is a multiplatform and user friendly application for students of ESL or EFL to learn the meanings and definitions of different terms and phrases.
Urban Dictionary - Urban Dictionary is a Web-based dictionary of slang words and phrases.
PronounceItRight - PronounceItRight, establishes order in the huge phonetic mess of global communications.
SlangLang - SlangLang is an editorial dictionary for slang words mainly used on the internet. Here you will find definitions and information about the origin and spread of terms, memes and emotes that are used on the net.
SlangSite.com - SlangSite.
The Online Slang Dictionary - Learn thousands of real slang words or add your own.