x–ray

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verb, often capitalized \ˈeks-ˌrā\

Definition of x–ray

transitive verb
: to examine, treat, or photograph with X-rays

See x–ray defined for English-language learners

See x–ray defined for kids

First Known Use of x–ray

1899

Other Medicine Terms

analgesia, angina, diabetes, hepatitis, homeopathy, logorrhea, palliate, pandemic

X–ray

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noun \ˈeks-ˌrā\

Definition of X–ray

1 : any of the electromagnetic radiations that have an extremely short wavelength of less than 100 angstroms and have the properties of penetrating various thicknesses of all solids, of producing secondary radiations by impinging on material bodies, and of acting on photographic films and plates as light does
2 : a photograph obtained by use of X-rays

X–ray

adjective

See X–ray defined for English-language learners

See X–ray defined for kids

First Known Use of x–ray

1896

Other Medicine Terms

analgesia, angina, diabetes, hepatitis, homeopathy, logorrhea, palliate, pandemic

X–RAY Defined for English Language Learners

x-ray

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verb

Definition of x–ray for English Language Learners

: to examine and make images of (things, such as the bones and organs inside the body) by using X-rays

X-ray

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noun

Definition of X–ray for English Language Learners

X-rays : powerful invisible rays that can pass through various objects and that make it possible to see inside things (such as the human body)
: an image that is created by using X-rays and that is usually used for medical purposes
: a medical examination that involves using X-rays

X–RAY Defined for Kids

x–ray

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verb , often cap X \ˈeks-ˌrā\

Definition of x–ray for Students

x–rayed

;

x–raying

: to examine, treat, or photograph with X-rays My arm was x-rayed for broken bones.

X–ray

play

noun \ˈeks-ˌrā\

Definition of X–ray for Students

1 : a powerful invisible ray made up of very short waves that is somewhat similar to light and that is able to pass through some solids and acts on photographic film like light
2 : a photograph taken by the use of X-rays an X-ray of the lungs

History for x–ray

In November, 1895, the German scientist Wilhelm Röntgen was conducting an experiment on the properties of electron tubes. He noticed that a fluorescent surface in the vicinity of the tube would light up even if shielded from the tube's direct light. A thick metal object would block some of the rays, while a less dense object such as wood would cast only a weak shadow. Röntgen's explanation was that the tube produced some type of invisible radiation that could pass through substances that blocked ordinary light. Because he did not know the nature of this radiation, he named it X-Strahl—translated into English as X-ray—based on the mathematical use of x to indicate an unknown quantity.