Simple Definition of first base
baseball : the base that must be touched first by a base runner; also : the position of the player who defends the area around first base
Full Definition of first base
1 : the base that must be touched first by a base runner in baseball
2 : the player position for defending the area around first base
3 : the first step or stage in a course of action <plans never got to first base>
Examples of first base in a sentence
a runner on first base
She hit a ground ball to first base.
He used to be a catcher, but now he plays first base.
First Known Use of first base
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