1) Xenon- xenon is an element with an atomic number of 54 and atomic weight of 131.29.
2) Xanthophyll- Xanthophyll is a class of carotenoids that are yellow pigments.
3) X-rays- X-rays are light rays with a wavelength from 0.01 to 1.0 nanometers.
4) Xenobiotic - Xenobiotic is any chemical that would not normally be found in a living organism or is produced by it.
5) X-Ray Spectrum - An x-ray spectrum is a set of x-ray frequencies emitted by a target in an x-ray tube.
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