Roentgen, Wilhelm


Wilhelm Conrad Rontgen (1845-1923), German-born, Dutch-educated physicist who first observed and documented X-rays on November 8, 1895. He made this seminal discovery by accident while experimenting with a set of cathode ray instruments. He was surprised to find a flickering image cast by his instruments separated from them by some distance. He knew that the image he saw was not being cast by the cathode rays (now known as beams of electrons) as they could not penetrate air for any significant distance.

A week later, he took an X-ray photograph of his wife’s hand which clearly revealed her wedding ring and her bones. The photograph electrified the general public and aroused great scientific interest in the new form of radiation. Roentgen called it “X” to indicate it was an unknown type of radiation. The name stuck, although (over Roentgen’s objections), many of his colleagues suggested calling them Roentgen rays. They are still occasionally referred to as Roentgen rays in German-speaking countries.

Roentgen did notable research in many fields of physics including the specific heats of gases, the thermal conductivity of crystals, the electrical and other characteristics of quartz, the influence of pressure on the refractive indices of various fluids, the modification of the planes of polarised light by electromagnetic influences, the variations in the functions of the temperature and the compressibility of water and other fluids, and the phenomena accompanying the spreading of oil drops on water. But when Roentgen received the Nobel Prize in Physics in 1901, the first Nobel Prize ever awarded in Physics, it was “in recognition of the extraordinary services he has rendered by the discovery of the remarkable rays subsequently named after him.”

Read Also:

  • Roentgenology

    Radiology, the science of radiation and, specifically, the use of both ionizing (like X-ray) and nonionizing (like ultrasound) modalities for the diagnosis and treatment of disease. Roentgenology is named for Wilhelm Conrad Roentgen who discovered X-rays. Roentgen, a professor of physics in Germany, wanted to prove his hypothesis that cathode rays could penetrate substances besides […]

  • Rohypnol

    The trade name for flunitrazepam, which has been abused as a ‘date rape’ drug. Rohypnol produces sedative-hypnotic effects including muscle relaxation and amnesia. It can produce physical and psychological dependence and can be lethal when mixed with alcohol and/or other depressants.

  • ROMA

    Representational oligonucleotide microarray analysis. A method for the detection of genomic aberrations between any two samples of DNA. ROMA measures the relative concentration of DNA in the two samples by hybridizing differentially labeled samples to a set of probes. By arraying oligonucleotide probes designed from the human genome sequence, and hybridizing with “representations” from the […]

  • Rooting reflex

    A reflex that is seen in normal newborn babies, who automatically turn the face toward the stimulus and make sucking (rooting) motions with the mouth when the cheek or lip is touched. The rooting reflex helps to ensure successful breastfeeding.

  • Rorschach test

    A common psychological test that involves using inkblots that show enigmatic and highly ambiguous shapes. Ten standardized blots are shown, one at a time, to a person, and the person’s responses are recorded, to determine what the person perceives about the inkblots.


Disclaimer: Roentgen, Wilhelm definition / meaning should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. All content on this website is for informational purposes only.