- the third in counterclockwise order of the bases from home plate.
- the playing position of the fielder covering the area of the infield near this base.
Origin of third base
An Americanism dating back to 1835–45
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for third base
He bunted the first ball, and it went foul over the third-base line.
Ken, attempting to sacrifice, rolled a little bunt down the third-base line and beat the throw.
Short-stop must be a quick and accurate thrower and a lively fielder, as he is required to back up second- and third-base.
If successful this play results in a safe hit, while the runner not infrequently makes, not only second, but third-base as well.
Another instance of team batting is when a runner is on third-base and the batsman signals that he will hit the next ball.