From Longman Dictionary of Contemporary Englishdesignated hitterˌdesignated ˈhitter noun [countable] DSBa baseball player who replaces the pitcher when it is the pitcher’s turn to hit the ball
Examples from the Corpus
designated hitter• That would allow the club to use Reggie Jefferson as a designated hitter.• Getting comfortable in his new role, he played six positions and was a designated hitter in 104 games.• I was a designated hitter there, and every day I got three or four ABs.• The Sox want Canseco, the designated hitter in 1995, to play right.• If flag art goes, then so does the designated hitter.• As with the designated hitter, there would be different rules in different leagues.From Longman Business Dictionarydesignated hitterˌdesignated ˈhitter noun [countable] American English informal someone who represents someone or does a job in their place 