first base

noun

Synonyms of first basenext
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 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
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.
On the field between home plate and first base, a thermometer read nearly 97 degrees before the game. Eva Andersen, CBS News, 2 July 2026 Of the three hitters who reached base against him, just one passed first base. Chandler Rome, New York Times, 2 July 2026 Machado, who was shifted over and essentially playing in the shortstop position, fielded the ball and diverted his route to go put a tag on Hoerner before making a tardy throw to first base. Kevin Acee, San Diego Union-Tribune, 30 June 2026 However, first base umpire Todd Tichenor tossed the agitated second baseman after Chisholm spiked his helmet toward home plate. Gary Phillips, New York Daily News, 29 June 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 5 Jul. 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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