The definition of an X-ray is a picture taken of the inside of something using high energy electromagnetic radiation with short wavelengths that can pass through items.(noun)
A picture that the doctor takes of your insides to see if you have any broken bones is an example of an X-ray.
To X-ray is also the act of examining, treating or photographing something using electromagnetic radiation.(verb)
An example of to X-ray is when the dentist uses an X-ray machine to find a cavity in a tooth.
See X-ray in Webster's New World College Dictionary
Origin: transl. of Ger x-strahl (< x, algebraic symbol for an unknown quantity + strahl, ray): so named by Wilhelm Konrad Roentgen (1895), because of its unknown character
See X-ray in American Heritage Dictionary 4
also X-raynoun also x ray or X ray
Origin: From the fact that it was a previously unknown form of radiation when first discovered.
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