As writers, it's important to know the origin of words and phrases in order to key in to the exact meaning you're trying to convey.

Etymology, or the study of the derivatives of words, is one of my favorite past times. It helps me group common words together and also helps in figuring out foreign words which becomes so easy once you know how.

Latin doesn't scare me and I laugh in the face of Greek suffixes, HA!

The referenced website has a search feature (which can be a bit cumbersome sometimes) as well as a resource section that links you to specialty dictionaries such as a Middle English dictionary or one just for jargon.