adjective
The ordinal form of the cardinal number three; Coming after the second.
noun
The person or thing in the third position.
One of three equal parts of a whole.
(uncountable) Ellipsis of third gear (of a gearbox).
(music) An interval consisting of the first and third notes in a scale.
(baseball) third base
(golf) A handicap of one stroke every third hole.
A third-class degree, awarded to the lowest achievers in an honours degree programme
(archaic) One sixtieth of a second, i.e., the third in a series of fractional parts in a sexagesimal number system.
verb
(informal) To agree with a proposition or statement after it has already been seconded.
To divide into three equal parts.