Free online dictionary web service ?

Is there any ? I googled but I wasn't so lucky !!!

How about this?

Dude,thanks a lot.It works well...i give you 5 stars ...btw,did you find any medical dictionary by chance or something ? also is this the only dictionary you found for free?

Tried googling but found nothing or that my keyword are rumbled.

I found this. Does it help?

Hack Sir, that does not appear to be a Web Service.

No,It's not.