extremizer

From extremize +‎ -er.

extremizer (plural extremizers)

1. (mathematics) A function that returns an extremum.
   • 2015, Shuanglin Shao, “On existence of extremizers for the Tomas-Stein inequality for ${\displaystyle S^{1}}$”, in arXiv‎^[1]:

     We also prove that any extremizer satisfies ${\displaystyle }$ for almost every ${\displaystyle x\in S^{1}}$.