noun🔗ShareRadioactivitéSpontaneous emission of ionizing radiation as a consequence of a nuclear reaction, or directly from the breakdown of an unstable nucleus."The old watch contained radium, which caused its hands to glow in the dark due to radioactivity. "La vieille montre contenait du radium, ce qui faisait briller ses aiguilles dans le noir en raison de la radioactivité.physicsenergysubstancechemistryenvironmentsciencematerialChat with AIVocabulary GamePractice Reading
noun🔗ShareRadioactivité, rayonnementThe radiation so emitted; including gamma rays, alpha particles, neutrons, electrons, positrons, etc."The radioactivity from the old smoke detector is dangerous and should be disposed of properly. "La radioactivité de l'ancien détecteur de fumée est dangereuse et doit être éliminée correctement.physicsenergysubstancescienceChat with AIVocabulary GamePractice Reading
