Noun has 2 senses

• third base(n = noun.artifact) third - the base that must be touched third by a base runner in baseball; "he was cut down on a close play at third"


• third base(n = noun.act) third - the fielding position of the player on a baseball team who is stationed near the third of the bases in the infield (counting counterclockwise from home plate); "he is playing third"