radioactivity
/ˌreɪdɪəʊakˈtɪvɪti/
radioactivity means spontaneous emission of ionizing radiation as a consequence of a nuclear reaction, or directly from the breakdown of an unstable nucleus. It carries an Arena rating of 1438, earned across 47 head-to-head judged battles.
Among words judged in Lexicurio's Arena, radioactivity ranks #454 of 17,124 for Most Sublime Words, #846 of 17,131 for Scariest Words, #1,429 of 17,138 for Most Incisive Words, #1,838 of 17,127 for Words That Escaped Their Books.
radioactivity is pronounced /ˌreɪdɪəʊakˈtɪvɪti/.
Why “radioactivity” is a great word
RADIOACTIVITY — [Noun] The spontaneous emission of ionizing radiation, such as alpha or beta particles or gamma rays, resulting from the decay of unstable atomic nuclei. From the prefix radio- (from Latin radius, "ray") combined with activity; coined circa 1898 by Marie Curie. Unlike "radiation" (a broad category including benign light and heat) or "fluorescence" (a surface-level echo of absorbed energy), radioactivity is an intrinsic, relentless nuclear disintegration. It is the silent, searing glow of a radium dial in a dark room, the faint, persistent click of a Geiger counter over ancient stone, and the invisible, enduring warmth of a buried ore—a testament to the profound instability woven into the very fabric of stable-seeming matter.
Etymology
From radioactive + -ity or radio- + activity.
noun
- Spontaneous emission of ionizing radiation as a consequence of a nuclear reaction, or directly from the breakdown of an unstable nucleus.e.g.“Today, no one would intentionally smear radioactive materials on their face, but in 1933, the dangers of radioactivity were not yet fully understood.” — 2020 March 8, Jacopo Prisco, “When beauty products were radioactive”, in CNN:
- The radiation so emitted; including gamma rays, alpha particles, neutrons, electrons, positrons, etc.
Definitions & examples from Wiktionary (CC BY-SA 3.0).
Words closest in meaning
By meaning, not spelling — each word's AI semantic fingerprint, nearest first.