من أفضل القواميس العلمية The Best Scientific Dictionaries

1. Word Reference 

http://www.wordreference.com/
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2. The Free Dictionary
http://www.thefreedictionary.com/
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3. Dictionary
http://www.dictionary.com/
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4. Cambridge Dictionary
http://dictionary.cambridge.org/
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5. Your Dictionary
http://www.yourdictionary.com/
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6. Longman Dictionary of Contemporary English Online
http://www.ldoceonline.com/
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7. Oxford Dictionaries
http://www.oxforddictionaries.com/
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8. Collins Dictionary
http://www.collinsdictionary.com/
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9. Almaany
http://www.almaany.com/
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10. Macmillan Dictionary
http://www.macmillandictionary.com/
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11. Merriam-Webster
http://www.merriam-webster.com/
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12. Acronym Finder
http://www.acronymfinder.com/
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13. Urban Dictionary
http://www.urbandictionary.com/
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14. Etymological Dictionary
http://www.etymonline.com/
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15. Vocabulary Dictionary
https://www.vocabulary.com/dictionary/
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16. Babylon
http://arabicdictionary.babylon-software.com/