About

Synopedia is a free thesaurus of English synonyms and antonyms. Every word has its own page, with its synonyms grouped by meaning, the most common first, its antonyms, usage labels (informal, formal, slang, dated), regional words and spellings (UK, US, Australian and other varieties of English), definitions and example sentences.

How the lists are made

The lists come from open sources (see Sources and licenses). A synonym is kept only if it shares the part of speech of the word, adjective with adjective, verb with verb, and if independent sources agree or a single source has proved reliable on samples checked by hand. The words are then grouped by meaning and sorted from the most common to the rarest, using their frequency in everyday English.

The pages are generated by a program, without a word-by-word human review. Mistakes are possible; please report them from the Contact page.

What the pages show

Besides synonyms and antonyms, a page may show a map of meanings, a scale from the weakest to the strongest word, short usage notes from classic synonym dictionaries now in the public domain, example sentences, the popularity of each word in printed books since 1850, the synonyms by length and the same word in the other languages of the site.

Synonym, antonym, opposite

A synonym is a word with a similar meaning, which can replace another word in a sentence. An antonym, also called an opposite, is a word with the opposite meaning. A word with several meanings often has different synonyms for each of them, hence the grouping by meaning.

Synopedia also exists in French, Italian, Spanish, German and Catalan.