objector

noun

1. A person who objects to something.

   “"It would be amusing, sir, to shut these various objectors up in a room and let them settle it among themselves."”

   “The Fife County Council, and other objectors, were successful in July [1950] in obtaining an interim interdict against this decision, but the Court of Session withdrew the interdict in January, and it was then stated that a civil court had no jurisdiction in the matter.”

   “But almost always such words are irreversibly established before the objectors learn of their existence, and the objections are hardly more than academic exercises.”