Written by the Fiveable Content Team โข Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examโขWritten by the Fiveable Content Team โข Last updated September 2025
Definition
AMU stands for Atomic Mass Unit. It is a unit used to measure the mass of atoms and subatomic particles. 1 AMU is approximately equal to the mass of a proton or neutron.