- German physicist: discoverer of x-rays 1895; Nobel Prize 1901.
- a unit of exposure dose that measures x-rays or gamma rays in terms of the ions or electrons produced in dry air at 0° C and one atmosphere, equal to the amount of radiation producing one electrostatic unit of positive or negative charge per cubic centimeter of air. Abbreviation: r, R
- of or relating to Wilhelm Roentgen, the Roentgen unit, or especially to x-rays.
- a unit of dose of electromagnetic radiation equal to the dose that will produce in air a charge of 0.258 × 10 –3 coulomb on all ions of one sign, when all the electrons of both signs liberated in a volume of air of mass one kilogram are stopped completely
- Wilhelm Konrad (ˈvɪlhɛlm ˈkɔnraːt). 1845–1923, German physicist, who in 1895 discovered X-rays: Nobel prize for physics 1901
