For comprehensive coverage:
* Merriam-Webster: A classic choice with an extensive dictionary and thesaurus, providing multiple definitions, example sentences, audio pronunciations, and word origins.
* Oxford English Dictionary (OED): The definitive source for English language, offering a historical perspective on words and their meanings, including etymology and usage examples from literature.
* Dictionary.com: A popular choice for its straightforward interface and comprehensive definitions, with a thesaurus integrated directly into each entry.
For user-friendliness and visual appeal:
* Vocabulary.com: An interactive site that provides definitions, synonyms, antonyms, and example sentences, incorporating fun quizzes and games to engage learners.
* Visuwords: A unique visual thesaurus that shows words in a network structure, revealing connections and relationships between terms, making it easy to explore related concepts.
For specialized needs:
* Wiktionary: A community-driven dictionary and thesaurus with a focus on providing detailed definitions, etymologies, and translations for multiple languages.
* Collins Dictionary: Known for its strong focus on contemporary English and its clear, concise definitions, making it a good choice for everyday use.
Additional factors to consider:
* Language options: Some sites offer a wider range of languages than others.
* Mobile apps: Many online dictionaries and thesauruses offer mobile apps for convenient access.
* Free vs. premium: Some websites offer basic features for free while charging for premium access to additional content or features.
Ultimately, the best online thesaurus and dictionary for you depends on your individual needs and preferences. Try out a few options to see which ones you find most helpful.