first base

noun

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

first baseman

-ˈbā-smən 

noun

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.

Recent Examples on the Web

Bregman goes to the Mets (and Mark Vientos slides over to first base) and Alonso goes to the Red Sox (and Triston Casas becomes a trade candidate). —Zach Pressnell, MSNBC Newsweek, 6 Nov. 2025

The Royals will continue to give him time behind the plate while also utilizing his ability to play first base. —Jaylon Thompson, Kansas City Star, 5 Nov. 2025

Some of their biggest needs include filling two outfield vacancies, upgrading the bullpen, finding a platoon option at third base and first base, and getting at least one more starting pitcher. —Chris Kirschner, New York Times, 3 Nov. 2025

Dominguez beat the outfielder to first base and was able to corral the throw for the final out of the inning. —Ryan Gaydos, FOXNews.com, 2 Nov. 2025

Word History

First Known Use

1848, in the meaning defined at sense 1

Rhymes for first base

• abase
• airspace
• apace
• backspace
• biface
• birthplace
• blackface
• boldface
• bookcase
• braincase
• briefcase
• carcase

Kids Definition

first base

noun

: the base that must be touched first by a base runner in baseball

also : the position of the player defending the area around first base