^33%JLS®yW@£lfllfi3&^ o a radiation leak from a nuclear power station 3^M63l®33?&2ii o radiation sick­ness $c33^ 0 the radiations emitted by radium ^Mfftl±J 63/&33^; 2 [U] heat, energy, etc. that is sent out in the form of rays HI 33 63      ( ^cf£jt# ) : ultraviolet radi­

ation ^h^3®33 0 electromagnetic radiation from power lines Efe^63EM3S33 3 (also ,radiation therapy) [u] the treatment of cancer and other diseases using radiation fkMff'fe — compare chemotherapy, radiotherapy

ra di ator /'reidieit8(r)/ noun 1 a hollow metal device for heating rooms. Radiators are usually connected by pipes through which hot water is sent. Kc ^  ^

)t: a central heating system with a radiator in each room    2 a

device for cooling the engine of a vehicle or an aircraft

(f) nm, 7m

radical /'raedikl/ adj., noun

madj. [usually before noun] 1 concerning the most basic and important parts of sth; thorough and complete If ;fc63; iu/ii63;   E5EI far-reaching: the need

for radical changes in education         JiS$^63

fnf Jc 0 demands for radical reform of the law #63ic4< 0 radical differences between the sexes W14|h] 63 2 new, different and likely to have a great

effect ^§]63; ^ It) 70$ 63: radical ideas ^ |s] nfi fill M ioo radical solution to the problem M E& I«1 H 63 Hr 63 jj 0 radical proposals % #| JE >63 ft iSC 3 in favour of thorough and complete political or social change $t$t 63; fill: the radical wing of the party % ft 63#?£

0 radical politicians/students/writers #j$:63®1nl5c/ # ffe / jfeM 4 (old-fashioned, NAmE, slang) very good filUff;

^      ► rad-ic-al-ly /-kli/ adv.: The new methods are

radically different from the old.  W

o Attitudes have changed radically.

m noun 1 a person with radical opinions       polit­ical radicals        2 (chemistry ffc) a group of

atoms that behave as a single unit in a number of compounds  i ill — see also free radical

,radical 'chic noun [u] fashionable left-wing views; the people, behaviour and way of life connected with these views       UM&U (

}

rad ic al ism /'raedikalizam/ noun [U] belief in radical ideas and principles

rad ical ize (BrE also -ise) /'raediklaiz/ verb [VN] to make people more willing to consider new and different policies, ideas, etc.; to make people more radical in their political opinions

sf j# ( J$L W. M M ) ; fk fflt ift: Recent events have radicalized opinion on educational matters, ft fx ffe 63

rad-icchio /rae'diikiau; NAmE -kiou/ noun [U] a type of chicory (= a leaf vegetable) with dark red leaves ^Pf

mn

radii pi. of radius

radio       /'reidiau; NAmE-ou/ noun, verb

mnoun 1 (often the radio) [U, sing.] the activity of broad­casting programmes for people to listen to; the programmes that are broadcast

i : The interview was broadcast on radio and tele­vision. rJjtfPO The play was written specially for radio.    ft ffn A

63 0 O I listen to the radio on the way to work. f£ ± SEE ± nff r ft o O Did you hear the interview with him on the radio ?  r ftMD/r 3\ A VS it 63 1* R ? o

local/national radio KfaA /      M O a radio

programme/station r If T/ / 7L n 2 [C] a piece of equipment used for listening to programmes that are broadcast to the public i&ialJl . to turn the radio on/ offfJZr / AAiMfJl o a car radio fJl o a radio

cassette player AlftWfit tt-f/l — see also clock radio 3 [U] the process of sending and receiving messages through the air using electromagnetic waves ftM ft^^Mit: He was unable to contact Blake by radio.       oto

keep in radio contact f£f#3c££7U7 ft o radio signals/ waves     IS4 [C] a piece of equipment, for

example on ships or planes, for sending and receiving radio signals        to hear a gale warning

on/over the ship’s radio f£$S±63       fJl^fgf!!

m verb (ra dio ing, ra-dioed, ra dioed) to send a message to sb by radio #it:    [V] The police

officer radioed for help. W&Rlft  „ 0 [VN] The

warning was radioed to headquarters. ilMA;^l;Efe|o]^nP ^tttiTWflL [also V that, VN that, VN to inf] radio- /’reidiau; NAmE -ou/ combining form (in nouns, adjectives and adverbs ffcj ft; % iSI , IB # IB ffl SI iB)

1                  connected with radio waves or broadcasting ft ^ 8tfi3; ?c^*rft63: radio-controlled

2                  connected with radioactivity fit M 63 ; H 63 : radiotherapy %t%lf?f£

radio-active /.reidiau’aektiv; NAmE -ou’aek-/ adj. sending out harmful radiation caused when the nuclei (= central parts) of atoms are broken up /&37I4 63; A IS 3163 ► radio-activ-ity /.reidiauaek’tivati; NAmE -ouaek-/ noun [U]: the study of radioactivity 0 a rise in the level of radioactivity ^I3ISI^631h3P .radio a stronomy noun [u] the part of astronomy that studies radio waves sent out by objects in space

'radio button noun (computing if) a small circle that you click on in order to make a particular choice. The radio button is then marked with a dot to show that it has been selected.

radio-car-bon /.reidiau'kaiban; NAmE -ou'kairb-/ noun [u] (;technical A i$) a radioactive form of carbon that is present in the materials of which living things are formed, used in carbon dating     ( 5^63 fXM14

IlHi# > 31 W ftj Ati W 63 ¥ fti ) : radiocarbon analysis

HkMi

.radiocarbon 'dating noun [u] (formal) = carbon

DATING

radio-chem-is-try /.reidiau’kemistri; NAmE -ou'k-/ noun [U] the area of chemistry which is concerned with radioactive substances Mt M it ^ ► radio-chem-ical /.reidiau'kemikl; NAmE -ou'k-/ adj.

.radio-con'trolled adj. controlled from a distance by radio signals 3n^&*63; ftmmM^63 radi og raph er /.reidi'Dgrafa(r); NAmE -'a:g-/ noun a person working in a hospital whose job is to take X-ray photographs or to use X-rays to treat some illnesses, such as cancer * X

radi og raphy /.reidi'Dgrafi; NAmE -'a:g-/ noun [u] the process or job of taking X-ray photographs * X radio-iso-tope /.reidiau'aisataup; NAmE .reidiou'aisa- toup/ noun (chemistry ft) a form of a chemical element which sends out radiation

radi-olo-gist /,reidi'Dlad3ist; NAmE -'a:la-/ noun a doctor who is trained in radiology 33 TIE A; X )tf463Elfe radi-ology /,reidi'Dlad3i; NAmE -'a:la-/ noun [U] the study and use of different types of radiation in medicine, for example to treat diseases   t£33E?r

radiometric /.reidiau'metrik; NAmE -diou-/ adj. relating to a measurement of radioactivity     33 iS ilJ

M63 ► radio-met-ric-ally /-ikli/ adv.: These rocks have been dated radiometrically at two billion years old. 'MfS

mmm,        20 {mm*

, radio- telephone noun a telephone that works by sending and receiving radio signals, used especially in cars, boats, etc.

.radio 'telescope noun a piece of equipment that receives radio waves from space and is used for finding stars and the position of spacecraft, etc. 33%Mjzsli radio ther apy /.reidiau'Berapi; NAmE -ou'Be-/ noun [u] the treatment of disease by radiation Wl 33 37 & : cl course of radiotherapy fit 33 ft 3§ — compare chemo­therapy ► radio-thera pist noun 'radio wave noun a low-energy electromagnetic wave, especially when used for long-distance commu­nication