(US politics) A member or supporter of a third party.

plural of third-grader

Used other than figuratively or idiomatically: see third, country. A country other than two specific countries, especially a country not party to an agreement between two other countries.

plural of Third Worlder

Somebody from the Third World.

plural of third country

plural of eighty-third

plural of fifty-third

plural of forty-third

plural of neutral third