When discussing baseball, the term "middle reliever" refers to a pitcher who comes into the game after the starting pitcher and before the closer. However, there are a few synonyms for this term that can be used interchangeably to describe the same type of pitcher. Some possible options include "setup man," "bridge reliever," "long reliever," and "fireman." Each of these terms describes the role of the pitcher in various ways, with "setup man" suggesting they are being set up for success in later innings and "bridge reliever" implying they are bridging the gap between the starting pitcher and closer. "Long reliever" indicates their ability to pitch for multiple innings, while "fireman" suggests they are being called upon to put out a potential rally or fire in the game.