definition of
reliever

[1] #1 reliever n. [stand-in, substitute, relief, backup, backup man, fill-in] someone who takes the place of another (as when things get dangerous or difficult); "the star had a stand-in for dangerous scenes"; "we need extra employees for summer fill-ins". wn

[2] #2 reliever n. [allayer, comforter] a person who reduces the intensity (e.g., of fears) and calms and pacifies; "a reliever of anxiety"; "an allayer of fears". wn

[3] #3 reliever n. [relief pitcher, fireman] a pitcher who does not start the game. wn