What is a Molecule? Definition and Usage

Meaning 1：basic unit of a compound (molecule)

molecule 🔊

/ˈmɒlɪkjuːl/

The smallest part of a substance, made up of two or more atoms joined together. It's like the tiniest building block that keeps the substance's properties.

Diagram of a water molecule (H2O) showing two hydrogen atoms bonded to one oxygen atom

basic unit of a compound 🔊

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/ˈbeɪsɪk ˈjuːnɪt əv ə ˈkɒmpaʊnd/

A molecule is the smallest particle of a substance that retains its chemical properties, composed of two or more atoms bonded together.

📁 Category：Objects & Materials 🔖 Level：Intermediate

📘 Details & Usage

📖 Root Explanation

Derived from Latin 'moles' (mass) + '-cule' (diminutive suffix), meaning a small mass.

💡 Mnemonic

Think of 'molecule' as 'mole' (mass) + 'cule' (small) – a tiny mass of atoms.

📖 Example

A molecule of water is made from just two hydrogen atoms and one oxygen atom. 🔊 A water molecule is composed of two hydrogen atoms and one oxygen atom.

🔗 Collocations

water molecule – a molecule composed of hydrogen and oxygen atoms

organic molecule – a molecule containing carbon, often found in living organisms

molecular structure – the arrangement of atoms within a molecule

🔄 Synonyms

particle (n.) – a minute portion of matter, which can include molecules

unit (n.) – a single component that is part of a larger system, similar to a molecule in chemistry

compound (n.) – a substance formed from chemically combined elements, consisting of molecules

🌱 Derivatives

molecular (adj.) – relating to or consisting of molecules

molecularly (adv.) – in a manner involving molecules

📖 Cultural Story

The term 'molecule' originates from French 'molécule', from Latin 'molecula', a diminutive of 'moles' (mass). It was adopted in chemistry to denote the smallest unit of a compound, reflecting the development of atomic theory.