xerophilic
Capable of growing and reproducing in very dry conditions.
X
X-rays
X-rays is the term used to describe the electromagnetic waves lying between the gamma radiation and UV-radiation ranges. X-rays have a wavelength of < 100 nm up to < 1 pm. The boundary zone between UV radiation and X-radiation (or Roentgen radiation, after the scientist who discovered X-rays) is not clearly defined, which is why we speak of wavelengths below 100 nm either as extreme UV rays or ‘soft’ X-radiation. X-rays belong to the category of ionising rays, and are thus subject to the (German) Radiation Protection Ordinance.
XUV
[Abbr. for extreme UV radiation] - Extreme UV radiation is the name given to the 100 to 1 nm range which - depending on the source - is also described as soft X-rays.