baseline

noun

base·​line ˈbās-ˌlīn How to pronounce baseline (audio)
Synonyms of baseline
often attributive
1
: a line serving as a basis
especially : one of known measure or position used (as in surveying or navigation) to calculate or locate something
2
a
: either of the lines on a baseball field that lead from home plate to first base and third base and are extended into the outfield as foul lines
b
: basepath
3
: a boundary line at either end of a court (as in tennis or basketball)
4
: a usually initial set of critical observations or data used for comparison or a control
5
: a starting point
the baseline of this discussion

Synonyms of baseline

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Examples of baseline in a Sentence

The experiment is meant only to provide a baseline for other studies. any year or event we use as the baseline for the Renaissance is going to be at least somewhat arbitrary
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.
Indeed, each national emergency has functioned like a ratchet, resetting the baseline size and reach of government ever higher. — Steve H. Hanke, Fortune, 1 July 2026 On Tuesday, French Open champion Alexander Zverev slipped worryingly on the baseline but was able to get straight back up. — Charlie Eccleshare, New York Times, 3 July 2026 Most chronic pain trials included people whose baseline sleep scores suggested sleep disturbance, but the studies did not separately analyze people with and without sleep problems. — Tom Gavin, EverydayHealth.com, 1 July 2026 Though the test established a technical baseline, advanced nuclear technology remains far from widespread commercial deployment. — Aman Tripathi, Interesting Engineering, 2 July 2026 See All Example Sentences for baseline

Word History

First Known Use

circa 1556, in the meaning defined at sense 1

Time Traveler
The first known use of baseline was circa 1556

Rhymes for baseline

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Browse Nearby Words

baselevel plain
baseline
baseliner
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Cite this Entry

“Baseline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/baseline. Accessed 8 Jul. 2026.

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Kids Definition

baseline

noun
base·​line ˈbās-ˌlīn How to pronounce baseline (audio)
1
: a line used as a base
2
a
: either of two straight lines on a baseball field leading from home plate to first base and third base and extending into the outfield
b
: base path

Medical Definition

baseline

noun
base·​line ˈbā-ˌslīn How to pronounce baseline (audio)
: a set of critical observations or data used for comparison or a control

More from Merriam-Webster on baseline

Nglish: Translation of baseline for Spanish Speakers

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