IdiomDictionary

This is a great Idiom Dictionary. Type in your word or phrase and the dictionary will give you all the options it has for those words. If you can not remember the exactly phrase you can also search alphabetically.

This is a fantastic tool for your students to explore the weird and wonderful idioms that existing within the English language. This could even be used as the basis for a 4 quiz to see which of your students has the best handle on the use of idioms in everyday language.

I like the way that you not only get a definition it also gives you an example of the idiom's use within a context.

http://www.idiomdictionary.com/