molecule

American  

[mol-uh-kyool] / ˈmɒl əˌkyul /

noun

1. Chemistry, Physics. the smallest physical unit of an element or compound, consisting of one or more like atoms in an element and two or more different atoms in a compound.

2. Chemistry. a quantity of a substance, the weight of which, measured in any chosen unit, is numerically equal to the molecular weight; gram molecule.

3. any very small particle.

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molecule British  

/ ˈmɒlɪˌkjuːl /

noun

1. the simplest unit of a chemical compound that can exist, consisting of two or more atoms held together by chemical bonds

2. a very small particle

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molecule Scientific  

/ mŏl′ĭ-kyo̅o̅l′ /

1. A group of two or more atoms linked together by sharing electrons in a chemical bond. Molecules are the fundamental components of chemical compounds and are the smallest part of a compound that can participate in a chemical reaction.

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molecule Cultural  

1. A combination of two or more atoms held together by a force between them. (See covalent bond and ionic bond.)

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Other Word Forms

• submolecule noun
• supermolecule noun

Etymology

Origin of molecule

First recorded in 1785–95; earlier molecula, from New Latin, from Latin mōlē(s) “mass” ( molar ² ( def. ) ) + -cula -cule ¹

Compare meaning

How does molecule compare to similar and commonly confused words? Explore the most common comparisons:

• formula unit vs. molecule

Example Sentences

Instead of removing fluorescence with a laser, they activated fluorescent molecules at a single point and tracked their movement.

From Science Daily

The scroll-like structure not only improves electrical conductivity and mechanical strength, but also changes how the material interacts with molecules.

From Science Daily

One type contains high amounts of aliphatic organic compounds, which are simple carbon-based molecules made of chains of carbon and hydrogen.

From Science Daily

Department of Energy has even referred to the fuel as “molecules of U.S. freedom.”

From The Wall Street Journal

“It is just going to be a building crescendo of who’s going to be able to get their molecules and who is not.”

From The Wall Street Journal

Related Words

• fragment
• particle