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molecule

/ˈmɒl.ɪ.kjuːl/
IELTSAcademic
noun

A molecule is the smallest part of a substance that can still exist on its own and keep the substance's chemical properties. It is made of two or more atoms joined together.

  • Water is made of molecules.
  • A molecule can be very small.

Adinary Nuance

A molecule is smaller and more exact than 'particle' in science. It is also more specific than 'atom', because a molecule has two or more atoms joined together. In everyday speech, people may say 'particle' loosely, but scientists usually say 'molecule' for a real chemical unit.

In other languages

Vietnamese
phân tử
Spanish
molécula
Chinese
分子
Japanese
分子
Korean
분자

Etymology

Molecule comes from French molécule, from Latin moles meaning 'mass' or 'small mass'. It entered English in the 17th century, first in scientific writing.

Common phrases

water moleculemolecule structuremolecule sizeorganic molecule

Synonyms

Related words

Frequently asked questions

Is a molecule the same as an atom?
No. An atom is one basic unit. A molecule has two or more atoms joined together.
Is molecule a formal word?
Yes. It is a scientific word used in study, research, and academic writing.
Can I use molecule in everyday English?
Yes, but mostly when talking about science, chemistry, or health.