baseline

noun

base·​line ˈbās-ˌlīn 

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

• alpha
• beginning
• birth
• commencement
• dawn
• day one
• genesis
• get-go
• git-go
• inception
• incipience
• incipiency
• kickoff
• launch
• morning
• nascence
• nascency
• onset
• outset
• start
• threshold

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

Between the first and second CAC scan, scores for women with a baseline of one to 99 rose by an average of eight points. —Maggie O'Neill, Health, 11 Apr. 2024

Using frameworks, like the National Association to Advance Black Birth's Black Birthing Bill of Rights, which helps provide a baseline of care, is a good way to do this. —A. Rochaun Meadows-Fernandez, Parents, 11 Apr. 2024

First, the platform, developed in collaboration with Stanford’s Crowdsourced Democracy Team, polls participants on the measures to establish a baseline. —Joe Mathews, The Mercury News, 6 Apr. 2024

Meanwhile, dozens of states and localities have hiked their minimum wages during the past several years, even as the federal baseline remains at $7.25 an hour — a rate that has remained frozen since 2009. —Aimee Picchi, CBS News, 29 Mar. 2024

Here, our testing shows a 5.6% reduction in latency compared with the baseline. —PCMAG, 27 Mar. 2024

During the first six months of Project Macoma’s operation, no alkaline water will be released as the company collects baseline data and tests safety controls. —IEEE Spectrum, 26 Mar. 2024

The state board’s staff calculated those estimates using a baseline period of 2017 to 2021 for comparison, and found that the 2040 reduction goals would mean a statewide reduction of about 500,000 acre-feet of water per year, roughly equivalent to the annual water use of Los Angeles. —Ian James, Los Angeles Times, 13 Mar. 2024

This year, the department withheld the usual 10% as a baseline, then subtracted another 7% to adjust for the decrease in relative poverty. —Nick Sullivan, The Arizona Republic, 29 Mar. 2024

Word History

First Known Use

circa 1556, in the meaning defined at sense 1

Kids Definition

baseline

noun

base·​line ˈbās-ˌlīn 

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 

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