www.merriam-webster.com
It is the online version of the well-known American Webster’s dictionary with the etimology of the words. It pronounces the words as well.
www.ldoceonline.com
It is the online version of The Longman Dictionary of Contemporary English with idioms and phrasal verbs. You can listen to the pronounciation of the words.
www.thefreedictionary.com
Here you can find medical dictionary, abbreviations, idioms and very interesing articles (the word of the day and the article of the day.) It pronounces the words.
www.dictionary.reference.com
It is a simple online dictionary with special topics such as the word of the day etc.
www.onelook.com
It is a simple online dictionary without any speciality.
www.webster-online-dictionary.org
It provides wide range of information about the searched words such as giving its etimology, special fields of use, synonyms, modern use and translations of the word.
http://startlap.dicfor.hu/szotar/hun/eng-hun/
It is a bilingual dictionary with pronounciation of the words.