valence

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valence

 [va´lens]
1. a positive number that represents the combining power of an element in a chemical compound, i.e., the number of bonds each atom of that element makes with other atoms. In this most general sense “valence” has been superseded by the concept “oxidation number.” However, “valence” is still used to indicate (1) the number of covalent bonds formed by an atom in a covalent compound or (2) the charge on a monatomic or polyatomic molecule.
2. in immunology, the number of antigen binding sites possessed by an antibody molecule, two per immunoglobulin monomer, or the number of antigenic determinants possessed by an antigen, usually a large number.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

va·lence

, valency (vā'lĕns, -len-sē),
The combining power of one atom of an element (or a radical), that of the hydrogen atom being the unit of comparison, determined by the number of electrons in the outer shell of the atom (v. electrons); for example, in HCl, chlorine is monovalent; in H2O, oxygen is bivalent; in NH3, nitrogen is trivalent.
[L. valentia, strength]
Farlex Partner Medical Dictionary © Farlex 2012

valence

(vā′ləns) also

valency

(-lən-sē)
n. pl. val·lences also val·lencies
1. Chemistry
a. The combining capacity of an atom or group of atoms as determined by the number of electrons it can lose, add, or share when it reacts with other atoms or groups. Also called oxidation state.
b. An integer used to represent this capacity, which may be given as positive or negative depending on whether electrons are lost or gained, respectively: The valences of copper are +1 and +2.
2. The number of binding sites of a molecule, such as an antibody or antigen.
3. The number of different antigens contained in a vaccine, corresponding to the number of pathogens that it is active against.
4. Psychology The degree of attraction or aversion that an individual feels toward a specific object or event.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

va·lence

, valency (vā'lĕns, -ē)
The combining power of one atom of an element (or a radical), that of the hydrogen atom being the unit of comparison, determined by the number of electrons in the outer shell of the atom (v. electrons); e.g., in HCl, chlorine is monovalent; in H2O, oxygen is bivalent; in NH3, nitrogen is trivalent.
[L. valentia, strength]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

va·lence

, valency (vā'lĕns, -sē)
The combining power of one atom of an element (or a radical), that of the hydrogen atom being the unit of comparison, determined by the number of electrons in the outer shell of the atom (v. electrons).
[L. valentia, strength]
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Both women had initially denied the scissors offence, but Valance changed her plea shortly before the trial.
Valance then began complaining about needing drugs, and both of them asked him for money to buy drugs.
The second half featured Bradfield, Shakin' Stevens, and Valance, the first Welsh chart-topper with Tell Laura I Love Her, in 1960.
" Now living and gigging on the Costa Blanca, Valance says he's enjoying life properly for therst " Now living and gigging on the Costa Blanca, Valance says he's enjoying life properly for therst time.
From the cotton fabric, cut one valance rectangle measuring 61/2"x the valance width.
Valance was joined by her property develop fiance Nick Candy who wore his trademark velvet green suit.
Aside from The Cowboys and Shane, fine Western films abound--The Searchers, The Outlaw Josey Wales, The Man Who Shot Liberty Valance to name only three--all of them stories about honor, courage, sacrifice, and what a man is expected to do not only by those around him but also by his own refined sense of what it means to be a man.
With Ouninpohja seeing no daylight when it mattered, the finish was fought out between Valance and Nessen Dorma.
Visually, the M6 differs from the 6 Series with a deeper front valance featuring big air intakes for the engine and brakes, the side sills are more contoured and the rear valance includes a diffuser.
The listing includes Superstar by Jamelia, Toxic by Britney, Kelis with Trick Me, and Joss Stone's Super Duper Love, as well as some older classics like Kylie's Spinning Around and Kiss Kiss by Holly Valance.
Taking design cues from the new high-performance M5 saloon, the Sport models can be identified by a new front bumper and valance with a wider air intake.
The most obvious change is the new rear lights or what designers call the car's "jewellery", and the deeper valance - taken from the sporty Type-R model.