Crowdin - Localize your product in a seamless way
Glosbe - Huge collaborative massively multilingual dictionary.
Google Translate - Google's free service instantly translates words, phrases, and web pages between English and over 100 other languages.
Wordnik - the biggest online English dictionary, by number of words
Reference.com - Reference.com is the #1 question answering service that delivers the best answers from the web and real people - all in one place.
VerbAce - VerbAce-Pro is an easy-to-use Desktop Translation Software. Translate in a mouse click