Definition: "Elite Eight" refers to either the last eight teams remaining in a given NCAA Tournament or the tournament's fourth round, when the last eight teams play for a chance to advance to the Final Four.
The NCAA Tournament starts with 65 teams. An Opening Round game narrows the field to 64. The first round halves the field to 32, and then those 32 teams meet and 16 -- the "Sweet Sixteen" -- advance.
The winners in the round of 16 are the "Elite Eight," and the winners in the Elite Eight are the "Final Four."
Examples:
"Davidson had a great run, but they couldn't get past Kansas in the Elite Eight.""At least one mid-major always makes the Elite Eight."

