radiation
n.-
1 energy waves or particles (n.) B2 Upper Intermediate Scienceenergy that moves through the air or space, like heat from a fire or light from the sun.
the process in which energy is emitted as particles or waves, including electromagnetic radiation such as light and radio waves.
ExampleThe sun's radiation provides the heat and light that plants need to grow.
ExampleThermal radiation allows heat to be transferred across a vacuum, which is why we can feel the warmth of the sun despite the empty space between us.
-
2 radioactive energy (n.) B2 Upper Intermediate Medicinedangerous energy produced by nuclear materials or X-ray machines.
ionising radiation emitted by radioactive substances or high-energy equipment, often associated with health risks or medical treatments.
ExampleThe workers wore special suits to protect themselves from radiation at the power plant.
ExampleThe patient underwent a course of targeted radiation to shrink the tumour before the surgical team attempted to remove it.
UsageOften used as an uncountable noun when referring to the general phenomenon of radioactivity.
Show 1 more senseShow fewer
-
3 evolutionary diversification (n.) C2 Proficiency Academic Technical Sciencethe process where one type of animal or plant quickly develops into many new species.
the rapid diversification of a lineage into several new forms that fill different ecological niches.
ExampleThe radiation of finches on the islands led to many different beak shapes.
ExampleThe fossil record provides clear evidence of a massive mammalian radiation following the extinction of the dinosaurs at the end of the Cretaceous period.
UsageCommonly appears in the phrase 'adaptive radiation'.
Borrowed from Latin radiatio, radiationis. By surface analysis, radiate + -ion.