Memrise is a Language learning Platform with a website and iOS and Android Apps.

Ludwig is a smart translator and linguistic search engine which helps you to find the perfect word or sentence to express your ideas.

StarDict is a free GUI released under the GPL for accessing StarDict dictionary files.

Wiktionary is a multilingual, web-based project to create a free content dictionary of all words in all languages.

Reference.com is an online encyclopedia.

Cram is an online platform to create and share online flashcards.

Wordnik is an online English dictionary and language resource that provides dictionary and thesaurus content.

Dictionary.com is an online dictionary platform.

Urban Dictionary is a crowdsourced online dictionary of slang words and phrases.

WordReference is an online translation dictionary for, among others, the language pairs English-French, English-Italian, English-Spanish, French-Spanish, Span…

dict.cc is a free, multilingual online dictionary. The site's database can also be downloaded and used offline.

Merriam-Webster is an online dictionary.

Wordo helps you find word definitions.