decline

American  

[dih-klahyn] / dɪˈklaɪn /

verb (used with object)

declined, declining

1. to withhold or deny consent to do, enter into or upon, etc.; refuse.

   He declined to say more about it.

   Synonyms:

   reject

2. to express inability or reluctance to accept; refuse with courtesy.

   to decline an invitation; to decline an offer.

3. to cause to slope or incline downward.

4. Grammar.

   1. to inflect (a noun, pronoun, or adjective), as Latin puella, declined puella, puellae, puellae, puellam, puella in the five cases of the singular.

   2. to recite or display all or some subset of the inflected forms of a noun, pronoun, or adjective in a fixed order.

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verb (used without object)

declined, declining

1. to express courteous refusal; refuse.

   We sent him an invitation but he declined.

2. to bend or slant down; slope downward; descend.

   The hill declines to the lake.

   Antonyms:

   rise

3. (of pathways, routes, objects, etc.) to follow a downward course or path.

   The sun declined in the skies.

4. to draw toward the close, as the day.

5. to fail in strength, vigor, character, value, etc.; deteriorate.

   Synonyms:

   languish, diminish, weaken, decay, degenerate

   Antonyms:

   improve

6. to fail or dwindle; sink or fade away.

   to decline in popularity.

7. to descend, as to an unworthy level; stoop.

8. Grammar. to be characterized by declension.

noun

1. a downward slope; declivity.

   Synonyms:

   hill

2. a downward movement, as of prices or population; diminution.

   a decline in the stock market.

3. a failing or gradual loss, as in strength, character, power, or value; deterioration.

   the decline of the Roman Empire.

   Synonyms:

   enfeeblement, degeneration, retrogression

4. a gradual deterioration of the physical powers, as in later life or in disease.

   After his seventieth birthday he went into a decline.

5. progress downward or toward the close, as of the sun or the day.

6. the later years or last part.

   He became an editor in the decline of his life.

decline British  

/ dɪˈklaɪn /

verb

1. to refuse to do or accept (something), esp politely

2. (intr) to grow smaller; diminish

   demand has declined over the years

3. to slope or cause to slope downwards

4. (intr) to deteriorate gradually, as in quality, health, or character

5. grammar to state or list the inflections of (a noun, adjective, or pronoun), or (of a noun, adjective, or pronoun) to be inflected for number, case, or gender Compare conjugate

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noun

1. gradual deterioration or loss

2. a movement downwards or towards something smaller; diminution

3. a downward slope; declivity

4. archaic any slowly progressive disease, such as tuberculosis

Related Words

See refuse ¹.

Other Word Forms

• declinable adjective
• decliner noun
• predecline verb (used with object)
• redecline verb
• undeclined adjective
• undeclining adjective

Etymology

Origin of decline

First recorded in 1275–1325; (verb) Middle English declinen, from Old French: “to inflect, turn aside, sink,” from Latin dēclīnāre “to slope, incline, bend”; compare Greek klī́nein “to lean” ( see lean ¹); (noun) Middle English declin, from Old French, derivative of decliner

Explanation

When something declines, it goes downhill. If you stop working out, your health may decline. If you want it to improve, you should start climbing inclines instead of coasting down declines. The verb decline means refuse to accept, but the noun decline means a downward slope (the opposite of an incline), or a decrease in quality. At the gym, the treadmill has an incline button to control how steep your climb is. Sadly, there's no button for decline, which would be much easier. Both words contain cline, or "to bend." The prefix tells you which way the bend goes. Decline implies a going, or turning, down.

Example Sentences

NewDays, a health-tech startup created by two former Google engineers, is betting that AI can empower people with dementia to seek out human contact and alleviate the isolation that often comes with—and exacerbates—cognitive decline.

From The Wall Street Journal • Apr. 18, 2026

In contrast, those who consumed refined olive oil tended to show a decline in microbiota diversity over time.

From Science Daily • Apr. 18, 2026

He had hoped the March international break would act as a reset for his side's poor form, but the decline has continued into April.

From BBC • Apr. 18, 2026

She found that when childcare costs rise, birth rates decline as well.

From Salon • Apr. 18, 2026

So catastrophic was the decline that the Siriono passed through a genetic bottleneck.

From "1491" by Charles C. Mann

Related Words

• decrease
• depreciate
• deteriorate
• diminish
• drop
• dwindle
• fail
• fall
• lower
• recede
• return
• sag
• shrink
• sink
• slide
• wane
• weaken
• worsen