Here's another useful Firefox keyword search. This time it's for Google glossary, which is great for looking up definitions of words.
In Firefox, bookmark this URL:
http://www.google.com/search?q=define:%s&sa=X&oi=glossary_definition
Then, when you need to look up a definition, just go to the address bar and type:
define [word]
[word] is the word you want to look up the definition for.
