noun, often attributive
base·​line | \ ˈbās-ˌlīn How to pronounce baseline (audio) \

Definition of baseline

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
2a : 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

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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

The average weight loss was 48 pounds, Terry says, and 98% of people were satisfied with the changes from their baseline. Karla Walsh, Woman's Day, "Everything You Need to Know About the Dubrow Diet," 29 Jan. 2019 Smith missed her first five 3-point tries before connecting from the baseline with 2:22 left in the third and finished with three 3s. Janie Mccauley, The Seattle Times, "Smith heats up in second half, Stanford back to Sweet 16," 25 Mar. 2019 From that baseline, Sanders has proposed a Social Security expansion, including higher cost-of-living adjustments and higher minimum benefit levels, that the liberal Tax Policy Center estimates will cost $188 billion over the next decade. Brian Riedl, Vox, "America might be ready for democratic socialism. It’s not ready for the bill.," 7 Aug. 2018 That was up from a baseline projection of three interest-rate increases before the tax cut passed. Nick Timiraos, WSJ, "WSJ Tax Guide 2019: The Tax Cut’s Economic Impact," 15 Feb. 2019 The next best price for a similar machine comes from HP itself for $789, though its own baseline model starts you out with the lesser Nvidia GeForce GTX 1050 with 2GB of video RAM compared to the above model’s 1050 Ti that features 4GB. Cameron Faulkner, The Verge, "At $599, HP’s gaming laptop is an even better deal for casual gamers," 18 Dec. 2018 Researchers then measured that parameter by feeding the participants or putting them on a treadmill, providing a baseline reading. Diana Gitig, Ars Technica, "Genetic information as self-fulfilling prophecy," 17 Dec. 2018 On this day, though, Kanepi took charge of baseline exchanges, compiling a 26-9 edge in winners, 14 on her favored forehand side alone. Fox News, "No. 1 seed Simona Halep loses in first-round at US Open," 27 Aug. 2018 Giorgi is also increasingly interested in pushing forward and taking advantage of the openings her baseline bolts can produce. Christopher Clarey, New York Times, "As Serena Williams Rolls, It’s Tempting to Think About No. 24," 9 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'baseline.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of baseline

circa 1556, in the meaning defined at sense 1

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Statistics for baseline

Last Updated

19 Apr 2019

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Time Traveler for baseline

The first known use of baseline was circa 1556

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More Definitions for baseline



English Language Learners Definition of baseline

technical : information that is used as a starting point by which to compare other information
: a line at either end of the playing area in games like basketball and tennis
: either one of the lines that lead from home plate to first base and third base


base·​line | \ ˈbā-ˌslīn How to pronounce baseline (audio) \

Medical Definition of baseline

: a set of critical observations or data used for comparison or a control

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Comments on baseline

What made you want to look up baseline? Please tell us where you read or heard it (including the quote, if possible).


marked by a state of overwhelming emotion

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