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

Polanco has never played first base in his career, but the Mets are going to start him there. —Ryan Canfield, FOXNews.com, 18 Dec. 2025

After France was traded to Toronto on July 31, one of nine deals the Twins made that week leading up to the deadline, Kody Clemens took most of the playing time at first base. —CBS News, 16 Dec. 2025

The Marlins also have Eric Wagaman and catcher Liam Hicks at first base and plan to give outfielder Griffin Conine some reps at first base in spring training, manager Clayton McCullough said. —Barry Jackson, Miami Herald, 12 Dec. 2025

The first base position is one that Nightengale gives two options for. —Drew Vonscio, MSNBC Newsweek, 11 Dec. 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