each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, leading to variation in atomic mass
예시들
Uranium-235 and uranium-238 are isotopes of uranium, playing crucial roles in nuclear fission reactions.
우라늄-235와 우라늄-238은 우라늄의 동위 원소로, 핵분열 반응에서 중요한 역할을 합니다.