onelook.com

Onelook.com.  This site checks several general purpose and many specialized dictionaries.

YOURDICTIONARY

 More than 400 dictionaries

 in more than 130 languages.

The Early Modern English

Dictionaries Database

127,000 word-entries from a dozen dictionaries from 1530 to 1657.

Websters Unabridged Dictionary:1913

bartleby.com

Type in the word and hear the

 correct way to pronounce it.

Merriam-Webster

All in One very handy.

allwords.com

Type in the word and hear the

 correct way to pronounce it.

public.iastate.edu

Pedro's Dictionaries

dictionary.com

Spell Check a Word spellex.com

Encarta World English Dictionary