WordNet® is a large lexical database of English with up to 140,000 entries and more than 1.4 million words, developed by the Cognitive Science Laboratory at Princeton University.

Chosen as "Best Dictionary App" by the book "Best Android Apps: The Guide for Discriminating Downloaders", O'Reilly Media.

Free Dictionary is an English Dictionary that gives you English definitions, synonyms, pronunciation and spelling.
- Auto-suggestion
- Offline Database query when there is no network
- Wikipedia Integration
- Play quiz game
- Searched word on Google Images
- Search history

This application allows you to browse off-line dictionaries. This is useful when the Internet connection is not availabe (abroad, in the plane...)

Offline English Arabic dictionary.
قاموس عربي إنجليزي
More than 83.400 words. FREE!

Online Dictionary - Multiple dictionaries including: English dictionary, medical dictionary, legal dictionary, financial dictionary, computer dictionary, thesaurus, dictionary of acronyms and abbreviations, dictionary of idioms, thesaurus, Columbia encyclopedia, Wikipedia encyclopedia, Hutchinson encyclopedia, examples from classic literature, pronunciations, word browser, glossary. Free access.

Application unofficial The Free Dictionary, thefreedictionary.

Advanced Dictionary allows you to translate in any direction between many world languages and allows you to test your knowledge.

Offline English French Dictionary. Dictionnaire Anglais Français.
More than 60.000 words. FREE!

Offline English Italian Dictionary. Dizionario Inglese Italiano.
More than 57.600 words. FREE!

Offline English-Spanish Dictionary. Diccionario Inglés-Español offline.
More than 85.900 words. FREE!

A simple English to English Dictionary.
With direct links to Google and Wikipedia for more details.

WordMate is an universal dictionary application.

http://wordmate.net

A game for both learners of the English language and for native English Speakers. This game of Hangman contains over 17 different topics. Also, includes a button that uses the google translate application to translate the word into the users language.

This is the basic version. it has two in game adds. The full version contains over 18 topics, over 600 words and will be updated regularly with new topics and words.

Offline English Hindi Dictionary. More than 27.400 words. FREE!

Offline English Greek dictionary. More than 37.500 words.
Αγγλο-Ελληνικό Λεξικό. Πάνω από 37.500 λέξεις. Δεν χρειάζεται σύνδεση στο internet!
FREE! ΔΩΡΕΑΝ!

Ultimate online dictionary with Wiki app for android 1.6+ Fully supports Moto Droid & Nexus 1. Can't find in dictionary? Find it on Wiki Wiki Wiki!

Features:
Droid & Nexus One Support
Text to Speech Keywords
Dictionary & Wiki as backup!
Dictionary Words Update Online
Dictionary find closest match
Now with THESAURUS!

Learn Spanish vocabulary with word cards, pronunciation by native Spanish speakers and exercises to test what you have learned.

+ Clear audio recordings of native Spanish speakers.
+ Very easy to use!
+ Works offline! (data rates while in roaming are expensive. No internet connection needed).
+ You can practice anywhere you go
+ Compressed files to ensure fast download anywhere.

Recommended app for tourists and business people visiting Spain.

Offline English Japanese Dictionary. Over 210.000 words and expressions!
英和辞書 offline。単語、成句、熟語を21万!
FREE!

Offline English Chinese Dictionary. 英漢字典.
More than 48.300 words. FREE!

English To Tamil Dictionary for Android Devices -Trail Version
With lot of Amazing options

A rich source of words for everyone who loves language, this free dictionary is both comprehensive and authoritative with its 123,000 words and 200,000 definitions based on the Collins Word Web - an unrivaled and constantly updated 2.5 billion-word database of today's English.