RhymeBook - RhymeBook is one of the best application that helps its users to find out the whole rhyme if they know some words of rhyme.
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WordReference - WordReference is a free online Oxford dictionaries for Spanish, French, Italian, German and more.
WordWeb - One-click lookup in any almost any Windows program; Hundreds of thousands of definitions and synonyms; The latest international English words; Works offline, or reference to Wikipedia and web references.