| HP | halogen phosphorus; handicapped person; haptoglobin; hard palate; Harvard pump; health profession(al... |
|---|---|
| HXIS | hard x-ray imaging spectrometry |
| SHHH | self-help for hard of hearing |
| cephalometric X-rays | <dentistry> An X-ray of the head that shows whether your teeth are aligned properly, and whether they are growing properly. (08 Jan 1998) |
|---|---|
| monochromatic rays | Light ray's or ionizing radiation of a very narrow band of wavelengths (ideally, of a single wavelength). Compare: photopeak, characteristic radiation. (05 Mar 2000) |
| W rays | Those between ultraviolet and X-ray's. Synonym: W rays. (05 Mar 2000) |
| cosmic rays | <radiobiology> High velocity particles of enormous energies, bombarding earth from outer space. It consists of protons and more complex atomic nuclei that, on striking the atmosphere, give rise to neutrons, mesons, and other less energetic radiation. (05 Mar 2000) |
| positive rays | Those originating in a gas discharge tube and moving in a direction opposite to that of cathode ray's; made up of positively charged ions. Synonym: positive rays. (05 Mar 2000) |
| primary rays | Cosmic ray's in the form in which they first strike the atmosphere, X-ray's generated at the focal spot of the tube. Synonym: direct rays. (05 Mar 2000) |
| X-rays | Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release energy - in the same energy range as gamma rays (0.010-10 mev), but of non-nuclear origin, of shorter wavelength than ultraviolet; soft X-rays or grenz rays are less penetrating and longer in wavelength than hard X-rays. (12 Dec 1998) |
| secondary rays | X-ray's generated when primary X-ray's impinge upon matter; scattered radiation. (05 Mar 2000) |
| H rays | <physics> A stream of hydrogen nuclei; i.e., protons. (05 Mar 2000) |
| soft rays | X-ray's of relatively long wavelength and slight penetrability. (05 Mar 2000) |
| Niewenglowski rays | Radiation emitted from a phosphorescent body after exposure to sunlight. (05 Mar 2000) |
| supersonic rays | Ray's with a wavelength higher than that perceptible to the human ear, above 20,000 Hz. (05 Mar 2000) |
| direct rays | Cosmic ray's in the form in which they first strike the atmosphere, X-ray's generated at the focal spot of the tube. Synonym: direct rays. (05 Mar 2000) |
| Dorno rays | The ultraviolet ray's with wavelengths below 289 nm; those biologically active. (05 Mar 2000) |
| indirect rays | X-ray's generated at a surface other than the anode target. (05 Mar 2000) |