Urban Dictionary - Urban Dictionary is a Web-based dictionary of slang words and phrases.
Silicon Valley Dictionary - Urban dictionary meets Silicon Valley
SlangSite.com - SlangSite.
FoxType Thesaurus - Visualize similar words for _____
Reverse Dictionary - Describe a concept and get back a list of words
Writefull Thesaurus - A Google Docs add-on that uses AI to give you synonyms