first base

noun

Synonyms of first basenext
1
: the base that must be touched first by a base runner in baseball
a runner on first base
2
: the player position for defending the area around first base
hit a ground ball to first base
3
: the first step or stage in a course of action
Plans never got to first base.
4
slang : amorous light touching or kissing
Unless the game has changed since I was a girl, first base was kissing …—Abigail Van Buren
—usually used in phrases like get to first base or reach first base
"It's true!" Pamela said. "If they talk about getting to first base, it means they held hands with their girl. …"—Phyllis Reynolds Naylor
compare home base sense 3, second base sense 3, third base sense 3

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
DeLuca missed his attempt at a diving catch on Christian Yelich’s one-out drive in the first inning with Jackson Chourio on first base. — ABC News, 24 Oct. 2026 But after starting his career as a catcher, he was moved by the Royals to first base in 1999. — Pete Grathoff, Kansas City Star, 22 Oct. 2026 The Guardians wouldn’t give up and had the go-ahead run at first base in the eighth when Kevin Kelly struck out Brayan Rocchio to leave the bases loaded after two runs scored. — Los Angeles Times, 20 Oct. 2026 The Rays challenged the calls at both first and second and Mesa was ruled safe when a video review overturned the out decision by first base umpire Mark Ripperger. — Rob Maaddi, Chicago Tribune, 14 Oct. 2026 See All Example Sentences for first base

Word History

First Known Use

1848, in the meaning defined at sense 1

Time Traveler
The first known use of first base was in 1848

Browse Nearby Words

Cite this Entry

“First base.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/first%20base. Accessed 27 Oct. 2026.

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

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