molecule
MOL-ih-kyool
Molecule (noun) means the smallest unit of a substance that keeps all its chemical properties, made of two or more atoms bonded together. Example: “A water molecule contains two hydrogen atoms and one oxygen atom.”
noun
1
The smallest unit of a substance that keeps all its chemical properties, made of two or more atoms bonded together.
"Clinical trials testing the molecule in humans have been underway for three years, Sinclair said."
— Sandee LaMotte, The ‘Benjamin Button’ effect: Scientists can reverse aging in mice. The goal is to do the same for humans (2022)
"A water molecule contains two hydrogen atoms and one oxygen atom."
"Scientists studied how the molecule reacted with light."
"Each molecule of sugar is made of carbon, hydrogen and oxygen atoms."
"Hydrogen chloride is a diatomic molecule, consisting of a hydrogen atom and a chlorine atom."
How to use molecule
Learner’s notesIn plain EnglishThe smallest building block of a chemical substance, formed from atoms bonded together.
Easily confused with
Common pairings
water molecule
DNA molecule
protein molecule
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Word forms
- Plural
- molecules, moleculae, moleculæ
Fill the gap
Can you complete this real example?
A water _____ contains two hydrogen atoms and one oxygen atom.
Etymology
Borrowed from French molécule, from New Latin molecula, a diminutive of Latin moles, "a mass."
Related words
Rhymes for molecule
See all rhymes for molecule →Frequently asked questions
What does “molecule” mean?
The word “molecule” means the smallest unit of a substance that keeps all its chemical properties, made of two or more atoms bonded together. In plain terms, the smallest building block of a chemical substance, formed from atoms bonded together.
How do you pronounce “molecule”?
“Molecule” is pronounced MOL-ih-kyool (/ˈmɑ.lɪ.kjul/ in IPA).
How do you use “molecule” in a sentence?
Here is “molecule” used in a sentence: “A water molecule contains two hydrogen atoms and one oxygen atom.”
What part of speech is “molecule”?
“Molecule” is a noun.
Where does the word “molecule” come from?
The word “molecule” comes from New Latin. Borrowed from French molécule, from New Latin molecula, a diminutive of Latin moles, "a mass.".
Is “molecule” a common word?
“Molecule” is an uncommon word in modern English, usually learned at around the B1 level.
What is the difference between a molecule and an atom?
An atom is the smallest unit of a chemical element, while a molecule is formed when two or more atoms bond together and represents the smallest unit of a substance that keeps its chemical properties. A molecule can be made of atoms of the same element or of different elements.
What is the difference between a molecule and a compound?
A molecule is any group of two or more bonded atoms, while a compound specifically refers to a molecule made of two or more different elements. Water is both a molecule and a compound, but oxygen gas (O2) is a molecule that is not a compound.
Why must a molecule have at least two atoms?
A molecule is defined by the bonding of atoms together, so a single, unbonded atom does not qualify as a molecule on its own. The bond between atoms is what gives a molecule its distinct chemical properties.
