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

Spinning waste into resources One target is the separation of strontium-90 and americium-241, radioactive isotopes that can have uses in medicine, manufacturing and advanced power systems. — Neetika Walter, Interesting Engineering, 18 Aug. 2026

Potatoes, beans, spinach, Brazil nuts, and many other foods naturally contain small amounts of radioactive isotopes. — Encyclopedia Britannica, 14 Aug. 2026

Next up will be looking at the meteorite's isotopes to figure out its connection to other meteorites formed early in Martian history. — Elizabeth Howell, Space.com, 11 Aug. 2026

The drug had been developed by ITM Isotope Technologies Munich SE, a long-standing player in the field of radiopharmaceuticals, which are an emerging treatment designed to shoot radioactive isotopes directly at tumor cells. — Ed Silverman, STAT, 11 Aug. 2026

Word History

Etymology

is- + Greek topos place

First Known Use

1913, in the meaning defined at sense 1

Rhymes for isotope

• antelope
• bronchoscope
• cantaloupe
• cystoscope
• endoscope
• envelope
• epitope
• gyroscope
• horoscope
• microscope
• misanthrope
• pericope

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