next after the second; being the ordinal number for three.

being one of three equal parts.

Automotive . of, pertaining to, or operating at the gear transmission ratio at which the drive shaft speed is greater than that of second gear for a given engine crankshaft speed, but not as great as that of fourth gear, if such exists

third gear.

rated, graded, or ranked one level below the second

He's third engineer on the ship.

a third part, esp. of one ( 1 / 3 ).

the third member of a series.

Automotive . third gear

Don't try to start a car when it's in third.

a person or thing next after second in rank, precedence, order

The writer of the best essay will receive a gold medal, the second a silver, and the third a bronze.

Usually, thirds. Law .

the third part of the personal property of a deceased husband, which in certain circumstances goes absolutely to the widow.

a widow's dower.

Music .

a tone on the third degree from a given tone (counted as the first).

the interval between such tones.

the harmonic combination of such tones.

Baseball . third base.

Usually, thirds. Commerce . a product or goods below second quality. Compare first ( def. 16 ) , second 1 ( def. 23 ) .

in the third place; thirdly.

adjective

tertian , tertiary , triennial

noun

trimester