Monolingual Dictionaries

Cambridge Advanced Learner's Dictionary - With clear definitions and useful study extras, this monolingual dictionary can help you on your way to becoming a confident, natural-sounding English speaker.

Cambridge Essential British English - With short definitions that are easy to understand, this monolingual dictionary is suitable for beginners and pre-intermediate students.             

Cambridge Learner's Dictionary - The ideal dictionary for intermediate learners of English.             

Webster’s Essential Mini Dictionary - With short definitions that are easy to understand, this monolingual dictionary is suitable for beginners and pre-intermediate students.             

Cambridge Business English Dictionary - A new monolingual dictionary of 35,000 business-related words, phrases and meanings designed to be used by business students and anyone using or encountering English in their work.             

Cambridge Academic Content Dictionary - With comprehensive coverage of key academic terms as well as a broad range of everyday meanings, this monolingual dictionary is perfect for intermediate and upper-intermediate students of American English.             

  • MacMillan Dictionary
  • Merriam-Webster Online - Online language information application with a dictionary, news, search engines, a translator, thesaurus, and medical dictionary search.
  • Roget's International Thesaurus of English Words and Phrases - with 85,000 hyperlinked cross-references, over 2,900 proverbs and quotations from classic and modern authors illustrate the 1,000-plus entries. 
  • The Free Dictionary - The world's most comprehensive dictionary: English, Spanish, German, French, Italian, Chinese, Portuguese, Dutch, Norwegian, Greek, Arabic, Polish, Turkish, Russian, Medical, Legal, and Financial Dictionaries, Thesaurus, Acronyms and Abbreviations, Idioms, Encyclopedia, a Literature Reference Library, and a Search Engine all in one!
  • Urban Dictionary - This is a crowdsourced online dictionary of slang words and phrases. At the start of 2014, the dictionary featured over seven million definitions.
  • Wiktionary - English-language Wiktionary, a collaborative project to produce a free-content multilingual dictionary. Designed as the lexical companion to Wikipedia, the encyclopaedia project, Wiktionary has grown beyond a standard dictionary and now includes a thesaurus, a rhyme guide, phrase books, language statistics and extensive appendices. We aim to include not only the definition of a word, but also enough information to really understand it. Thus etymologies, pronunciations, sample quotations, synonyms, antonyms and translations are included.
  • WordReference offers the Concise Oxford English Dictionary with more than 240,000 words, phrases, and meanings, a testament to its world-class standards. In addition to definitions, the Concise Oxford English Dictionary provides rich detail into the etymology of words in the English language, as well as helpful usage tips for those learning English.
  • Wordsmyth - The Wordsmyth Dictionary-Thesaurus Suite now includes antonyms, real audio pronunciations, new images and animations, thousands of new example sentences, a new entry presentation, and more.
  • yourDictionary - A very easy to use online dictionary.

Bilingual & Multilingual Dictionaries

WordReference.com
Online Dictionaries

Dictionary Look up: 

  • bab.La - Diccionarios (inglés, alemán, francés y portugués) con sinónimos, frases comunes, pronunciación y ejemplos.
  • Diccionarios.com -> Diccionarios de Lengua española, sinónimos y antónimos, conjugador verbal,  ideológico, Español-Inglés, English-Spanish, Español-Francés, Français-Espagnol, Español-Alemán, Deutsch-Spanisch, Castellano-Catalán y Català-castellà.
  • Linguee - The Linguee search results are divided into two sections. On the left hand side you see results from our reliable editorial dictionary. This provides you with a quick overview of various translations of your search term. On the right hand side, you see example sentences from other sources to give you an idea of how your search term has been translated in context.
  • Reverso - Translate words and idioms. Type a word or several words in the translation search engine and instantly get a variety of examples of use taken from real-life situations (movie dialogs, news articles, etc.) and from official documents.
  • Ultralingua - Dictionary, Language Tools - Incluye definiciones y traducciones a alemán, español, francés, italiano, latín o portugués.
  • Wiktionary, the free dictionary - Multilingual dictionary with more than one million entries with English definitions from over 295 languages.

Specific Dictionaries

Abbreviations
  • Abbreviations and acronyms dictionary - With more than 900,000 human-edited definitions, Acronym Finder is the world's largest and most comprehensive dictionary of acronyms, abbreviations, and initialisms.

American English

Finances

  • Financial Dictionary - It provides concise definitions of 8,000 terms with 18,000 useful links. This information comes from the world of banking and investing, providing users with thorough and reliable meanings to all the most common, and even uncommon, financial terms

Food

Medicine

  • Medical Dictionary Online - A free online medical dictionary search engine for definitions of medical terminology, pharmaceutical drugs, healthcare equipment, health conditions, medical devices, specialty terms and medical abbreviations.

Phrasal verbs

Pictures

  • The Internet Picture Dictionary - English, French, German, Italian & Spanish. Browse by letter or by category. With activities such as Flashcards, Fill-in-the-blanks, Word Scramble, Stinky Spelling or Straight Recall.

Pronunciation

  • Howjsay - A free online Talking Dictionary of English Pronunciation. When your entry appears in pink, mouse over to hear it pronounced. More than 160000 entries in the dictionary.
  • Forvo - All the words in the world. Pronounced.

Quotations

  • Bartleby Quotations - Different collections of quotations: Familiar, Prose and Poetical, Practical, Proverbs, Maxims, etc.

Rhyming & Poetry

Synonyms

  • Synonyms - Synonyms Thesaurus with Antonyms & Definitions

Tourism