isotope

noun

iso·​tope ˈī-sə-ˌtōp 

1

: any of two or more species of atoms of a chemical element with the same atomic number and nearly identical chemical behavior but with differing atomic mass or mass number and different physical properties

2

: nuclide

isotopic

ˌī-sə-ˈtä-pik  -ˈtō- 

adjective

isotopically

ˌī-sə-ˈtä-pi-k(ə-)lē  -ˈtō- 

adverb

Examples of isotope in a Sentence

Recent Examples on the Web

Unlike nuclear fission – which splits atoms and creates dangerous radioactive waste – fusion uses hydrogen isotopes (like tritium and deuterium) and produces helium as a harmless byproduct. —New Atlas, 22 Dec. 2024

The idea is that a telltale sign of a very advanced alien technology would fuse the hydrogen isotope of deuterium, which unlike normal hydrogen contains a neutron in its nucleus, into helium to produce massive amounts of energy. —Bruce Dorminey, Forbes, 13 Dec. 2024

These hydrogen isotopes will then combine through nuclear fusion, and in that process release neutrons. —Chris Baraniuk, WIRED, 27 Nov. 2024

By analyzing the dust, ash, oxygen isotopes, and air bubbles preserved in ice cores, scientists could now reconstruct the history of Earth’s climate. —The New Yorker, 28 Oct. 2024

Word History

Etymology

is- + Greek topos place

First Known Use

1913, in the meaning defined at sense 1

Kids Definition

isotope

noun

iso·​tope ˈī-sə-ˌtōp 

: any of the forms of an element that differ in the number of neutrons in an atom

isotopic

ˌī-sə-ˈtäp-ik 

-ˈtō-pik

adjective

isotopically

-ˈtäp-i-k(ə-)lē 

-ˈtō-pi-

adverb

Medical Definition

isotope

noun

iso·​tope ˈī-sə-ˌtōp 

1

: any of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behavior but with differing atomic mass or mass number and different physical properties

2

: nuclide

isotopic

ˌī-sə-ˈtäp-ik  -ˈtō-pik 

adjective

isotopically

-ˈtäp-i-k(ə-)lē  -ˈtō-pi- 

adverb

isotopy

ˈī-sə-ˌtō-pē  ī-ˈsät-ə-pē 

noun

plural isotopies