Online Dictionaries
English-English Dictionaries
Use English-English dictionaries when you have a word in English and you want to know the meaning in EnglishCambridge Dictionaries
Choose in their drop-down box from several options such as British English, American English, Business English. With audio
Merriam-Webster
American English. With audio
OneLook
British English and American English. Looks in up to 40 different dictionaries
Wiktionary
Also has many other languages
Urban Dictionary
Dictionary of slang
EnglishClub Slang
With explanation, sample sentences and quiz
EnglishClub Phrasal Verbs
With explanation, sample sentences and quiz
Synonym Dictionaries (thesauruses)
Use synonym dictionaries to find words that mean the same or very nearly the same, for example: fast/quick/speedy/swiftRhymeZone
Select "Find synonyms" in the drop-down menu
Antonym Dictionaries
Use antonym dictionaries to find words that mean the opposite, for example: fast/slowRhymeZone
Select "Find antonyms" in the drop-down menu
Syllable Dictionaries
Tools to help you calculate the number of syllables in a word or sentence, and where they start and endRhyming Dictionaries
Use rhyming dictionaries to find words that have endings that sound the same, for example: understand/motherland or rain/pain Rhymer
Finds various types of rhymes
RhymeZone
Select "Find rhymes" in the drop-down menu
Glossaries
Glossaries are alphabetical lists of words related to a particular topic and giving basic definitionsChat Abbreviations Glossary
Short forms used in chat rooms, texting etc and what they mean
Grammar Terms Glossary
List of words used to talk about grammar and their meanings
Pronunciation Terms Glossary
List of words used to talk about pronunciation and their meanings
TEFL Terms Glossary
For teachers, a glossary of terms used in teaching English and their definitions