If you need to know what a word means as fast as possible, go to Definr. It’s not as accurate or as thorough as Merrium-Webster, but it will help you cut to chase and get a usable result quickly and for free.
The content is based on Princteon’s open WordNet 2.0 and according to the site’s creators, they can serve up a word entry in just 2.4 miliseconds depending upond the user’s internet connection. And what’s the most common word searched for at Definr? “Hello”.