A game in which a pitcher allows the opposing team no hits.

Also known as a No-No. A baseball game in which the pitcher throws all nine innings and does not allow a single official hit. Can be jinxed if some moron in the audience (whether live, radio or TV) mentions the words "no-hitter".

a game where no batter gets to base by hitting, but may get there because the pitcher walks a batter or accidentally hits the batter with a pitch

an entire game pitched without allowing a base hit to the opposing team

In baseball, a no-hit game (familiarly known as a no-hitter, and sometimes called a no-no for "no hits no runs") refers to a contest in which at least one of the teams has prevented the other from getting an official hit during the entire length of the game, which must be at least 9 innings (27 outs) by the current Major League Baseball definition.