All relevant matters: told each other everything. (pronoun)
The most important fact or consideration: In business, timing is everything. (pronoun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "everything" in a sentence
"You go on myspace and read everything, and you read all their friends, and you know * everything*. danah: Stigma."
"I look at the screen and I see this character who is the hero of a action-comedy space opera, and I know that everything I see, *everything* I see, I see because writers and actors and directors wanted me to see this."
"Apparently when everything around me is quiet, my brain decides to make up for the silence and think and over analyze everything "