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

Their work showed that when oxygen is limited, red blood cells use glucose to generate a molecule that helps release oxygen to tissues.

From Science Daily

The study, published in Nature Communications, found that small fat-based molecules known as epoxy-oxylipins act as natural regulators of the immune response.

From Science Daily

In cancer immunotherapy, tumor derived molecules called antigens are paired with immune stimulating compounds known as adjuvants.

From Science Daily

This cassette specifically targets resistance genes carried on plasmids, which are small circular DNA molecules that replicate inside bacterial cells.

From Science Daily

The journey began with T3p, a small RNA molecule detected in breast cancer but not in normal tissue.

From Science Daily

Related Words

• fragment
• particle