White House tapes: Secret audio recordings made by President Nixon in his office that were eventually subpoenaed during investigations into the Watergate scandal.
18½ minute gap: A portion of one of President Nixon's White House tapes where there was mysteriously missing audio for approximately 18 and a half minutes.
Saturday Night Massacre: The name given to the events on October 20, 1973, when President Nixon fired Watergate special prosecutor Archibald Cox and Attorney General Elliot Richardson resigned in protest.