ENGLISH
REFERENCE

dalton

n. countable
C1 Advanced US //ˈdɔɫtən// dal·ton

n. a tiny unit used to measure the mass of atoms and molecules. It is based on the weight of a single carbon atom.

n. a unit of atomic mass equal to one twelfth of the mass of a carbon-12 atom. Used primarily in chemistry and physics to express molecular weights.


SIMPLE

The atomic mass of oxygen is about 16 daltons.

CONTEXTUAL

Scientists measure the size of large proteins in daltons to understand their structure.

Origin

From Old English dæl (“valley”) + tun (“settlement”). Equivalent to dale + town.

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