noun

astigmatism

uh-STIG-muh-tiz-uhm

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Astigmatism (noun) means In optics, astigmatism is a defect of a lens where light rays from a single point fail to meet at one focal point, so the resulting image is blurred. Example: “The lens had a slight astigmatism that softened the edges of every photo.”

noun

optics In optics, astigmatism is a defect of a lens where light rays from a single point fail to meet at one focal point, so the resulting image is blurred.

"The lens had a slight astigmatism that softened the edges of every photo."

"Engineers corrected the astigmatism in the telescope's mirror before it was installed."

pathology In medicine, astigmatism is a vision disorder, usually caused by a misshapen cornea, in which light does not focus correctly on the retina and the image appears blurred.

"Her optician diagnosed mild astigmatism during the eye test."

"Glasses can correct astigmatism by compensating for the cornea's uneven curve."

"He'd had astigmatism since childhood, so distant signs always looked slightly smeared."

How to use astigmatism

Learner’s notes

In plain EnglishAstigmatism is a blurring effect caused by light not meeting at a single sharp point, whether in an eye or in a lens.

When to use it

It is a technical term from optics and medicine, most often met at the optician's or in scientific writing.

Memory tip

The related word stigma shares the same Greek root but means something quite different, so don't let the spelling mislead you.

Trace the full origin ↓

Easily confused with

stigma →

Common pairings

mild astigmatism correct astigmatism astigmatism in the cornea lens astigmatism

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C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

C2 · Advanced serendipity Fortunate discoveries made entirely by accident.

Gen Z slang rizz Charm — the ability to attract a romantic interest.

B2 · Intermediate empathy The capacity to share another person’s feelings.

C1 · Advanced nonchalant Casually calm and relaxed; unconcerned.

Internet slang delulu Delusional — believing something against the odds.

Etymology nostalgia Greek nostos “return home” + algos “pain”.

Test yourself on “astigmatism” A quick quiz — meaning, synonyms & usage →

Fill the gap

Can you complete this real example?

The lens had a slight _____ that softened the edges of every photo.

Etymology

The word combines the negative prefix a- with a form of the Ancient Greek stigma, meaning mark or point, and the suffix -ism, so it literally suggests the absence of a single point. It was coined by the English polymath William Whewell in 1846.

Origin: Ancient Greek (via English coinage)

Synonyms

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astigmia

Rhymes for astigmatism

rheumatism aposematism

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Frequently asked questions

What causes astigmatism in the eye?

It is usually caused by a misshapen cornea, which stops light focusing correctly on the retina and blurs the image.

Who coined the term astigmatism?

The English polymath William Whewell coined it in 1846.

Can astigmatism affect things other than the eye?

Yes, the same term describes a defect in any lens, such as in a camera or telescope, where light rays fail to meet at one focal point.

What is the meaning of astigmatism?

"astigmatism" (noun) means in optics, astigmatism is a defect of a lens where light rays from a single point fail to meet at one focal point, so the resulting image is blurred.