regression

noun

re·​gres·​sion ri-ˈgre-shən 

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

Synonyms

• retrogression
• reversion

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

Like any good Chinese math problem, this distinctly American form of regression toward the mean can be quantified. —Peter Hessler, The New Yorker, 1 Apr. 2024

With the complications of mast cell activation syndrome, including drops in blood pressure, flushing, severe itching and rashes, Ms. Banks relied on alternative therapies, including reiki, hypnosis, emotional freedom technique, quantum healing and regression therapy. —Alex Williams, New York Times, 27 Mar. 2024

The ceiling is some wacky AL East regression for all the teams and all of a sudden the Blue Jays have won the division. —Daniel Kohn, SPIN, 27 Mar. 2024

Joining them in the fight against these regressions and gaps are Gladstone, Chloé Zhao, Emma Corrin, Eva Longoria, Greta Gerwig, Jane Campion, Janicza Bravo and Lilly Wachowski, who will serve on the selection committee and determine the 8 filmmakers who will take part in the program. —Angelique Jackson, Variety, 25 Mar. 2024

The map now shows in detail the expansion or regression of tiger territories, and exactly where has been surveyed when, instantly highlighting data gaps. —Rebecca Cairns, CNN, 15 Mar. 2024

All of this back-and-forth loop created a lot of redundant work, many regressions and constant delays. —Joel Montvelisky, Forbes, 28 Feb. 2024

If the regression is merely incremental, count the Wolverines as fortunate. —Jon Wilner, The Mercury News, 30 Jan. 2024

There should be some regression to the mean as the schedule lightens up. —The Courier-Journal, 25 Jan. 2024

Word History

First Known Use

1583, in the meaning defined at sense 1

Phrases Containing regression

• linear regression
• multiple regression

Kids Definition

regression

noun

re·​gres·​sion ri-ˈgresh-ən 

: an act or the fact of regressing

Medical Definition

regression

noun

re·​gres·​sion ri-ˈgresh-ən 

: 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 childhood

—Havelock Ellis