Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “radioactivity”

radioactivity

noun [U] uk   /ˌreɪ.di.əʊ.ækˈtɪv.ɪ.ti/ us    /-oʊ.ækˈtɪv.ə.t̬i/
the quality that some atoms have of producing energy, which can be very harmful to health the energy produced by atoms in this way: A dangerous amount of radioactivity was released into the environment last month.
(Definition of radioactivity from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of radioactivity?
Add Cambridge dictionaries to your browser to your website

Definitions of “radioactivity” in other dictionaries

Word of the Day

look on the bright side

to find good things in a bad situation

Word of the Day

The language of work

by Kate Woodford,
October 15, 2014
Most of us talk about our jobs. We tell our family and friends interesting or funny things that have happened in the workplace (=room where we do our job), we describe – and sometimes complain about – our bosses and colleagues and when we meet someone for the first time, we tell

Read More 

life tracking noun

October 20, 2014
the use of one or more devices or apps to monitor health, exercise, how time is spent, etc.

Read More