ExpertGlossary terms starting with R

2,379 terms

radiation field Synonym far-field region.
Radiation Fog A fog that forms when outgoing longwave radiation cools the near-surface air below its dew point temperature.
Radiation Gas A mixture of photons and fast-moving charged particles.
Radiation Hardening Protection of a particular system, subsystem, or component from functional damage due to the effects of nuclear (or other) radiation by shielding the…
Radiation hybrid A hybrid cell containing small fragments of irradiated human chromosomes. Maps of irradiation sites on chromosomes for the human, rat, mouse, and other…
radiation hybrid cell panel (Abbreviation: RH). A somatic cell hybrid panel in which the chromosomes from the species of interest have been fragmented by irradiation prior to cell…
Radiation Laws The four physical laws which fundamentally describe the behavior of blackbody radiation: Kirchhoff's law, Planck's law, Stefan-Boltzmann law and Wien's…
radiation mode For an optical fiber, an unbound mode. Note: In an optical fiber, a radiation mode is one having fields that are transversely oscillatory everywhere…
radiation necrosis (RAY-dee-AY-shun neh-KROH-sis) The death of healthy tissue caused by radiation therapy.
radiation nurse A health professional who specializes in caring for people who are receiving radiation therapy.
Radiation Oncologist (RAY-dee-AY-shun on-KAH-loh-jist) A doctor who specializes in using radiation to treat cancer.
radiation pattern The variation of the field intensity of an antenna as an angular function with respect to the axis.
radiation physicist A person who makes sure that the radiation machine delivers the right amount of radiation to the correct site in the body.
radiation resistance The resistance that, if inserted in place of an antenna, would consume the same amount of power that is radiated by the antenna.
radiation scattering The diversion of radiation (thermal, electromagnetic, or nuclear) from its original path as a result of interaction or collisions with atoms, molecules…
radiation security Measures to defend against TEMPEST attacks [CESG].
radiation surgery (RAY-dee-AY-shun SER-juh-ree) A type of external radiation therapy that uses special equipment to position the patient and precisely give a single large…
radiation therapist A health professional who gives radiation treatment.
Radiation Therapy (RAY-dee-AY-shun THAYR-uh-pee) The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and…
Radiation-Dominated Universe When the density of radiation is greater than that of any other component.
radiation-hardened fiber An optical fiber made with core and cladding materials that recover, within a specified period of time, a specified percentage of their intrinsic…
Radiational Cooling The cooling of the Earth's surface. At night, the Earth suffers a net heat loss to space due to terrestrial cooling.
Radiational Inversion Used interchangably with Nocturnal Inversion; a temperature inversion that develops during the night as a result of radiational cooling of the surface.
Radiative Cooling The process of cooling by which a heat absorbing media absorbs heat from one source and radiates the heat away.
Radiative Forcing Radiative forcing is the change in the net vertical irradiance (expressed in Watts per square metre: Wm-2) at the tropopause due to an internal change or…
radiative heating rate The heating rate due to the divergence of long and shortwave radiative flux; this is a calculated quantity using the state of the atmospheric and…
Radiative Zone A layer of the Sun lying between the core and convection zone where energy travels outward through the slow radiation, absorption, and re-radiation of…
Radiator A room heat delivery (or exchanger) component of a hydronic (hot water or steam) heating system; hot water or steam is delivered to it by natural…
Radiator Vent A device that releases pressure within a radiator when the pressure inside exceeds the operating limits of the vent.
RADIC System Rapidly Deployable Integrated Command and Control System.
Radical cure (also: radical treatment) Complete elimination of malaria parasites from the body; the term applies specifically to elimination of dormant liver stage…
radical cystectomy (RA-dih-kul sis-TEK-toh-mee) Surgery to remove all of the bladder (the organ that holds urine) as well as nearby tissues and organs.
radical hysterectomy (RA-dih-kul HIS-teh-REK-toh-mee) Surgery to remove the uterus, cervix, and part of the vagina.
radical local excision (RA-dih-kul LOH-kul ek-SIH-zhun) Surgery to remove a tumor and a large amount of normal tissue surrounding it. Nearby lymph nodes may also be removed.
radical lymph node dissection A surgical procedure to remove most or all of the lymph nodes that drain lymph from the area around a tumor.
radical mastectomy (RA-dih-kul ma-STEK-toh-mee) Surgery for breast cancer in which the breast, chest muscles, and all of the lymph nodes under the arm are removed.
radical nephrectomy (RA-dih-kul neh-FREK-toh-mee) Surgery to remove an entire kidney, nearby adrenal gland and lymph nodes, and other surrounding tissue.
radical perineal prostatectomy (RA-dih-kul PAYR-ih-NEE-ul PROS-tuh-TEK-toh-mee) Surgery to remove all of the prostate through an incision between the scrotum and the anus.
radical prostatectomy (RA-dih-kul PROS-tuh-TEK-toh-mee) Surgery to remove the entire prostate. The two types of radical prostatectomy are retropubic prostatectomy (surgery…
radical retropubic prostatectomy (RA-dih-kul reh-troh-PYOO-bik PROS-tuh-TEK-toh-mee) Surgery to remove all of the prostate and nearby lymph nodes through an incision in the wall of the…
Radical treatment See radical cure.
radical vulvectomy (RA-dih-kul vul-VEK-toh-mee) Surgery to remove the entire vulva (the external female genital organs, including the clitoris, vaginal lips, and the opening…
radicle The portion of the plant embryo which develops into the primary root.
RADINT Radar Intelligence.
radio 1. Telecommunication by modulation and radiation of electromagnetic waves. 2. A transmitter, receiver, or transceiver used for communication via…
radio access system controller A controller that supports the wireless mobility management and wireless access call control functions.
radio altimeter Radionavigation equipment, on board an aircraft or spacecraft, used to determine the height of the aircraft or the spacecraft above the Earth's surface or…
radio and wire integration (RWI) The combining of wire circuits with radio facilities. [JP 1-02]
radio baseband See baseband.
radio beam A radiation pattern from a directional antenna, such that the energy of the transmitted electromagnetic wave is confined to a small angle in at least one…
Radio Blackout (RBO) The complete disruption of radio (or radar) signal over large areas caused by the ionization accompanying a high altitude nuclear explosion, especially…
radio buttons A group of selectable components in which only one component may be selected. Selection of one of the group causes the previously selected component to be…
radio channel An assigned band of frequencies sufficient for radio communication. Note 1: The bandwidth of a radio channel depends upon the type of transmission and the…
radio channel privacy An encryption treatment applied to signaling or user data, which treatment is intended to prevent an unauthorized detector of the data from extracting…
radio common carrier (RCC) A telecommunications common carrier that provides radio communications services but is not engaged in the business of providing landline local exchange…
radio control The remote control of an apparatus by signals conveyed by electromagnetic waves.
radio detection The detection of the presence of an object by radiolocation without precise determination of its position. [JP 1-02]
radio detection and ranging See radar.
radio direction-finding [RDF] Radiodetermination using the reception of radio waves for the purpose of determining the direction of a station or object. [NTIA] [RR]
radio direction-finding station A radiodetermination station using radio direction-finding. [NTIA] [RR]
Radio Emission Emissions of the sun in radio wavelengths from centimeters to dekameters, under both quiet and disturbed conditions. Type I.
radio equipment As defined in Federal Information Management Regulations, any equipment or interconnected system or subsystem of equipment (both transmission and…
Radio Event Flares with Centimetric Bursts and/or definite Ionospheric Event (SID)
radio facility The bearer/signaling connection between the radio port intermediary and the radio port controller. [T1.Rpt34-1994]
radio fadeout See flutter.
radio field intensity Synonym field strength.
radio fix The locating of a radio transmitter by bearings taken from two or more direction finding stations, the site of the transmitter being at the point of…
radio frequency See RF.
radio frequency assignment See frequency assignment.
radio frequency channel assignment Synonym frequency assignment.
Radio Frequency Identification (RFID) Technology that uses low-powered radio transmitters to read data stored in a transponder (tag).
radio frequency interference (RFI) Synonym electromagnetic interference.
radio horizon The locus of points at which direct rays from an antenna are tangential to the surface of the Earth.
radio horizon range (RHR) The distance at which a direct radio wave can reach a receiving antenna of given height from a transmitting antenna of given height.
radio interface The common boundary between a mobile station and the radio equipment in the network, which is the boundary defined by functional characteristics, physical…
radio net An organization of radio stations that is capable of direct communication on a common frequency. 2.
radio paging The use of a pocket-size radio receiver capable of alerting its wearer that there is a phone call, either from a displayed phone number or to a…
radio personal terminal (RPT) A light-weight, pocket-size portable radio terminal (or "personal terminal") providing the capability for the user to be either stationary or in motion…
radio port A unit that supports transmission of signals over the air interface. [After T1.Rpt34-1994]
radio port controller A controller that provides an interface between one or more subtending radio port intermediaries and a PCS switching center, and supports air interface…
radio range The distance from a transmitter at which the signal strength remains above the minimum usable level for a particular antenna and receiver combination. 2.
radio range station A radionavigation land station in the aeronautical radionavigation service providing radial equisignal zones.
radio recognition and identification See identification, friend or foe.
Radio Regulations As used in legal documents, the latest (i.e., as of the document date) ITU Radio Regulations to which the United States is a party.
Radio Regulations Board A permanent organization of the International Telecommunication Union (ITU) that implements frequency assignment policy and maintains the Master…
radio relay The reception and retransmission by a radio station of signals that are received either from another radio station or from a wire, fiber optic, microwave…
radio relay system A point-to-point radio transmission system in which signals are received, conditioned, and retransmitted by one or more intermediate radio stations.
radio telegraphy The transmission of telegraphic codes by means of radio. [JP 1-02]
radio telephony The transmission of speech by means of modulated radio waves. [JP 1-02]
radio teletypewriter (RTTY) A teletypewriter employed in a communication system using radio circuits. Note: Such systems are spoken of as RATT systems.
radio termination (RT) A device or functionality that terminates radio transmissions, performs radio channel management, provides rate adaptation between the radio channel and…
radio watch shift Synonym area broadcast shift.
radio wave An electromagnetic wave of a frequency arbitrarily lower than 3000 GHz. Synonym Hertzian wave.
Radio Waves Electromagnetic radiation with a wavelength greater than 1 mm (beyond infrared).
radio-coverage diagram A diagram that shows the area within which a radio station is broadcasting an effective signal strength in relation to a given standard.
radio-wire integration See radio and wire integration.
radioactive (RAY-dee-oh-AK-tiv) Giving off radiation.
Radioactive (or Nuclear) Cloud An all-inclusive term for the volume of hot gases, smoke, dust, and other particulate matter from the nuclear weapon itself and from its environment, that…
Radioactive dating A technique for estimating the age of an object by measuring the amounts of various radioisotopes in it.
radioactive drug (RAY-dee-oh-AK-tiv...) A drug containing a radioactive substance that is used in the diagnosis and treatment of cancer and in pain management of bone…