The person or thing in the third position. / One of three equal parts of a whole. / (uncountable) The third gear of a gearbox. / (music) An interval consisting of the first and third notes in a scale.

(informal) To agree with a proposition or statement after it has already been seconded. / To divide into three equal parts.

plural of third

A third helping of food for one person, or refill of coffee or other drink.

Third-person singular simple present indicative form of third

(neuroanatomy, anatomy) One of the four connected ventricles of the mammalian brain

plural of third ventricle

plural of third grade

(politics) A socialist ideology, originating in Trotskyism, which aims to support the organised working class, as opposed to capitalism, or another prominent force, originally Stalinism and in the 1990s and 2000s often Islamism.

(language education, grammar) A structure used to talk about unreal or unfulfilled events in the past, containing an "if" clause (with a verb in the past perfect) and a main clause (with would + the bare perfect infinitive of a verb).