relapse

American  

[ri-laps, ri-laps, ree-laps] / rɪˈlæps, rɪˈlæps, ˈri læps /

verb (used without object)

• relapses,
  present (3rd person singular)
• relapsed,
  past participle,  past
• relapsing
  present participle

1. to fall or slip back into a former state, practice, etc..

   to relapse into silence.

2. to fall back into illness after convalescence or apparent recovery.

3. to fall back into vice, wrongdoing, or error; backslide.

   to relapse into heresy.

   Synonyms:

   lapse, revert, regress

---

noun

• relapses
  plural

1. an act or instance of relapsing.

2. a return of a disease or illness after partial recovery from it.

relapse British  

verb

1. to lapse back into a former state or condition, esp one involving bad habits

2. to become ill again after apparent recovery

---

noun

1. the act or an instance of relapsing

2. the return of ill health after an apparent or partial recovery

Other Word Forms

Derived Forms

• relapser
  noun
• relapsable
  adjective
• unrelapsing
  adjective

Inflected Forms

Nouns

• relapses
  plural

Participles

• relapsing
  present
• relapsed
  past

Conjugated Forms

Present

• relapse
  simple
• relapses
  simple
• have relapsed
  perfect
• has relapsed
  perfect
• am relapsing
  progressive
• are relapsing
  progressive
• is relapsing
  progressive
• have been relapsing
  perfect progressive
• has been relapsing
  perfect progressive

Past

• relapsed
  simple
• had relapsed
  perfect
• was relapsing
  progressive
• were relapsing
  progressive
• had been relapsing
  perfect progressive

Future

• will relapse
  simple
• will have relapsed
  perfect
• will be relapsing
  progressive
• will have been relapsing
  perfect progressive

Etymology

Origin of relapse

First recorded in 1400–50; (for the verb) late Middle English, from Latin relāpsus “slid back,” past participle of relābī “to slide back, revert,” from re- re- + lābī “to fall, slide, make a mistake”; noun derivative of the verb

Explanation

A relapse is a decline, especially of someone's health. If your grandmother survived cancer only to have it return two years later, you could say she suffered a relapse. Relapse implies that someone has recovered from an illness and slid back into a worse state, like when you are getting over a cold but then you suddenly feel bad all over again. Unwanted behavior can also be described this way; if you find yourself biting your nails again, it's a nail-biting relapse. The Latin word relabi is the root of relapse, slip back.

Example Sentences

See Examples For:

relapse relapses relapsed relapsing

After a major relapse, and at Bartlett’s urging, she set up an online fundraiser to ease the financial strain of medical treatment.

From Los Angeles Times ● Oct. 7, 2026

These effects could potentially contribute to greater mood stability and a lower risk of relapse.

From Science Daily ● Sep. 8, 2026

“Despite advances in treatment, an unmet need remains for oral therapies that can deliver robust relapse prevention, slow disability progression, while maintaining a favorable safety profile,” Novartis Chief Medical Officer Shreeram Aradhye said.

From The Wall Street Journal ● Sep. 1, 2026

Japan will ease overtime regulation starting Tuesday in a move meant to help spur economic growth but criticised as a relapse into the country's ingrained workaholic culture.

From Barron's ● Sep. 1, 2026

He’s suffered a relapse, I thought; he is back in his delirium.

From "Z for Zachariah" by Robert C. O’Brien

But, the trial, in five NHS trust areas, found it did not stop patients suffering relapses, and some critics say there needs to be further research into its effectiveness.

From BBC ● Aug. 26, 2026

The European Commission approved Cenrifki for secondary progressive multiple sclerosis without relapses.

From The Wall Street Journal ● Jun. 23, 2026

"If a patient relapses and needs another hospital admission, that's costly too," Mons points out.

From Science Daily ● Mar. 11, 2026

If a patient relapses or breaks a rule in a rehab facility, the knee-jerk impulse should not be to discharge them from the program.

From Slate ● Dec. 19, 2025

Sometimes, when I have relapses of my old demon, I lie in the crook of his arm and he comforts me this way, talking to me all night long to stave off the bad dreams.

From "The Poisonwood Bible" by Barbara Kingsolver

Maya, 13, from Hythe in Kent, was diagnosed with neuroblastoma at three years old, but relapsed in 2023 having been in remission for five years.

From BBC ● Sep. 20, 2026

Future studies will use animal models and larger patient groups to better understand how drug delivery, tumor structure, and lysosomal storage interact in clinical settings, including in relapsed cancers.

From Science Daily ● Mar. 27, 2026

The Food and Drug Administration has accepted a biologics license application for anito-cel as a fourth-line treatment for patients with relapsed or refractory multiple myeloma.

From Barron's ● Feb. 23, 2026

This means that patients had relapsed after trying different immunotherapies.

From The Wall Street Journal ● Oct. 27, 2025

When informed of this, he stopped and said Tally-ho, what?” in a feeble voice, then relapsed into silence.

From "The Once and Future King" by T. H. White

In 2025, Italy became the first country to pass a national law recognising obesity as a chronic, progressive and relapsing disease.

From BBC ● Jul. 25, 2026

This allowed them to identify traces of several pathogens, including Yersinia pestis, the bacterium responsible for plague, and Borrelia recurrentis, which causes louse borne relapsing fever.

From Science Daily ● Jul. 8, 2026

But now, almost a decade later, the Times looks to be relapsing into bad form.

From Salon ● Apr. 6, 2026

Jebb emphasised that GLP-1 drugs "are a really valuable tool in obesity treatment -- but obesity is a chronic relapsing condition."

From Barron's ● Jan. 7, 2026

"Alive," she echoes, as if she were relapsing to her old quoting days.

From "How the García Girls Lost Their Accents" by Julia Alvarez

Related Words

• recidivism
• recurrence
• regression
• worsening