x-unit

American  

[eks-yoo-nit] / ˈɛksˌju nɪt /

noun

1. a unit formerly used to express the wavelength of x-rays and gamma rays, equal to approximately 10− 11 centimeters. Xu, XU

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x-unit British  

noun

1. a unit of length equal to 0.100 202 × 10 ^–12 metre, for expressing the wavelengths of X-rays and gamma rays

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