valence

¹ American  

[vey-luhns] / ˈveɪ ləns /

noun

1. Chemistry. Also valency

   1. the quality that determines the number of atoms or groups with which any single atom or group will unite chemically.

   2. the relative combining capacity of an atom or group compared with that of the standard hydrogen atom. The chloride ion, Cl–, with a valence of one, has the capacity to unite with one atom of hydrogen or its equivalent, as in HCl or NaCl.

2. Immunology. the number of determinants per molecule of antigen.

3. the capacity of one person or thing to react with or affect another in some special way, as by attraction or the facilitation of a function or activity.

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Valence ² American  

[va-lahns] / vaˈlɑ̃s /

noun

1. a city in and the capital of Drôme, in SE France.

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Valence ¹ British  

/ valɑ̃s /

noun

1. a town in SE France, on the River Rhône. Pop: 64 260 (1999)

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valence ² British  

/ ˈveɪləns /

noun

1. another name (esp US and Canadian) for valency

2. the phenomenon of forming chemical bonds

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valence Scientific  

/ vā′ləns /

1. A whole number that represents the ability of an atom or a group of atoms to combine with other atoms or groups of atoms. The valence is determined by the number of electrons that an atom can lose, add, or share. An atom's valence is positive if its own electrons are used in forming the bond, or negative if another atom's electrons are used. For example, a carbon atom can share four of its electrons with other atoms and therefore has a valence of +4. A sodium atom can receive an electron from another atom and therefore has a valence of −1. (In this book the distinction between positive and negative valences is ignored unless it is relevant.) The valence of an atom generally indicates how many chemical bonds it is capable of forming with other atoms.

2. Also called valence number oxidation state

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valence Cultural  

1. A number characterizing an atom, equal to the number of valence electrons.

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Etymology

Origin of valence

First recorded in 1865–70; from Latin valentia “strength, worth,” equivalent to present participle valent- (stem of valēns ) “to be strong” + -ia noun suffix; -ence

Explanation

The valence of an atom is the ability of that atom, expressed in numbers, to combine or interact with another atom, depending on the number of electrons available for bonding in the atom’s outer shell, called the valence shell. The Latin valentia, "strength," is the basis for the word valence. It's a fitting word, as the valence of an element determines its strength — an idea that was first recorded in the later 19th century. Since the word valence carries the idea of interaction, it can also be used to describe the amount of attraction or repulsion by people, either toward each other or an event.

Example Sentences

At the center of the discovery is a carbene, a form of carbon with just six valence electrons.

From Science Daily • Apr. 11, 2026

Excitons form inside semiconductors when electrons absorb energy and jump from their resting state in the valence band to a higher energy state in the conduction band.

From Science Daily • Jan. 22, 2026

When we talk about something in economic terms, it really doesn’t have much moral valence.

From Los Angeles Times • Sep. 9, 2025

Audiences from all backgrounds found valence to a story that I found to be more about assimilation than antisemitism.

From Los Angeles Times • May 29, 2024

Egged on by scheming courtiers and generals, relations between Atawallpa and Washkar spent several years swinging through the emotional valence from concealed suspicion to overt hostility.

From "1491" by Charles C. Mann

Related Words

• reactiveness
• reactivity