What are some alternatives?
When comparing Lingoes and The Online Slang Dictionary, you can also consider the following products
Dictionary.com - Dictionary.com is the world’s leading digital dictionary. We provide millions of English definitions, spellings, audio pronunciations, example sentences, and word origins.
GoldenDict - The program has the following features: Use of WebKit for an accurate articles' representation, complete with all formatting, colors, images and links.
Slang-Dictionary.org - Slang-Dictionary is a web-based database for searching through the database of slang words and learn how different words are getting different meanings in different countries of the world.
Google - Google Search, also referred to as Google Web Search or simply Google, is a web search engine developed by Google. It is the most used search engine on the World Wide Web
Urban Dictionary - Urban Dictionary is a Web-based dictionary of slang words and phrases.
Linguee - English Dictionary and Translation Search with 1,000,000,000 example sentences from human translators. Languages: English, German, French, Spanish, and Portuguese