molecule

[ mol-uh-kyool ]

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.

molecule

/ 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

molecule

/ 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.

molecule

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

Other Words From

• sub·mole·cule noun
• super·mole·cule noun

Word History and Origins

Origin of molecule¹

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

Word History and Origins

Origin of molecule¹

C18: via French from New Latin mōlēcula, diminutive of Latin mōlēs mass, mole ⁴

Example Sentences

Perhaps certain gene networks and signaling molecules act as individuals at the level of the cell, while others are spread out between cells.

From Quanta Magazine

Strikingly, if the flies are fed antioxidants that neutralize these molecules, it does not matter if they never sleep again.

From Quanta Magazine

They might perfume the air by releasing small molecules that smell like a whiff of strawberries, perhaps.

From Science News For Students

As water heats up, individual water molecules move faster and faster.

From Science News For Students

Ions — molecules that have a charge — move between these electrodes in a material called an electrolyte.

From Science News For Students

Each type of atom and molecule has its own unique spectrum, according to the rules of quantum mechanics.

From The Daily Beast

Specifically, it targets a molecule called VEGF that sends signals that promote the growth of blood vessels.

From The Daily Beast

And those examples are a molecule in the atom bomb of the Internet.

From The Daily Beast

Every fructose molecule in sucrose, in contrast, is bound to a glucose.

From The Daily Beast

A molecule of carbon dioxide traps heat, radiant heat, the long wave end of the spectrum.

From The Daily Beast

Pete, after spewing the last hateful molecule away, reversed his tiny fibre engines, and began to draw in.

From Project Gutenberg

Does not the soul which animates us endure by the same right as each molecule of oxygen or nitrogen or iron?

From Project Gutenberg

The foreign protein is changed by splitting its molecule into its simplest parts and then recombining them in the desired form.

From Project Gutenberg

Each molecule of silver chromate forms two silver ions when it is ionized.

From Project Gutenberg

This brings selenophene more akin to pyrrole than thiophene, but the group -NH- in the molecule of pyrrole is an auxochrome.

From Project Gutenberg

Related Words

• fragment
• particle