regression

noun

re·​gres·​sion ri-ˈgre-shən How to pronounce regression (audio)
1
: the act or an instance of regressing
2
: a trend or shift toward a lower or less perfect state: such as
a
: progressive decline of a manifestation of disease
b(1)
: gradual loss of differentiation and function by a body part especially as a physiological change accompanying aging
(2)
: gradual loss of memories and acquired skills
c
: reversion to an earlier mental or behavioral level
d
: a functional relationship between two or more correlated variables that is often empirically determined from data and is used especially to predict values of one variable when given values of the others
the regression of y on x is linear
specifically : a function that yields the mean value of a random variable under the condition that one or more independent variables have specified values
3
: retrograde motion

Examples of regression in a Sentence

the regression to really childish behavior that boys often undergo when put in large groups
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.
Virgin is, as its name suggests, a purposeful regression, a return to youthful possibility. Spencer Kornhaber, The Atlantic, 27 June 2025 Barring a regression — or a late-season surge from someone else — these two should be neck and neck. Kalen Lumpkins, Chicago Tribune, 27 June 2025 The strategist found that putting those six variables into a logit model — a regression calculation that is simple by Wall Street standards — performed better than using an artificial intelligence model with similar inputs, as well as several other modeling approaches. Jesse Pound, CNBC, 26 June 2025 This historical regression was mirrored recently in 2013 when Supreme Court Chief Justice John Roberts issued a controversial decision in Shelby County v. Holder, which effectively reversed key provisions of the 1964 Voting Rights Act. Ed Gaskin, Boston Herald, 18 June 2025 See All Example Sentences for regression

Word History

First Known Use

1583, in the meaning defined at sense 1

Time Traveler
The first known use of regression was in 1583

Browse Nearby Words

Cite this Entry

“Regression.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/regression. Accessed 16 Jul. 2025.

Kids Definition

regression

noun
re·​gres·​sion ri-ˈgresh-ən How to pronounce regression (audio)
: an act or the fact of regressing

Medical Definition

regression

noun
re·​gres·​sion ri-ˈgresh-ən How to pronounce regression (audio)
: a trend or shift toward a lower, less severe, or less perfect state: as
a
: progressive decline (as in size or severity) of a manifestation of disease
tumor regression following radiation
b(1)
: a gradual loss of differentiation and function by a body part especially as a physiological change accompanying aging
menopausal regression of the ovaries
(2)
: gradual loss (as in old age) of memories and acquired skills
c
: reversion to an earlier mental or behavioral level or to an earlier stage of psychosexual development in response to organismic stress or to suggestion
a protective regression towards childhoodHavelock Ellis

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