Definition of valency in English:

valency

noun

British
Chemistry
  • 1The combining power of an element, especially as measured by the number of hydrogen atoms it can displace or combine with:

    ‘carbon always has a valency of 4’
    Compare with valence
    • ‘Plutonium has five different crystal-type conditions or ‘phases’ that it can be in, and has five possible valencies.’
    • ‘The degree of flocculation, and hence randomness of particle orientations on sedimentation, generally increases with the concentration and valency of the cations in the solution.’
    • ‘It is well-known that aggregation can be induced by changes in pH, the salt concentration, valency of ions, or the polarity of the solvent.’
    • ‘The higher the valency of the counterions, the more significant is the reversal of the effective charge of the aggregates.’
    • ‘Depending on the charges of additional groups that may be bound to the phosphate group, phospholipids in water can have a valency between - 2 and + 1, and also neutral groups are possible.’
    1. 1.1Linguistics The number of grammatical elements with which a particular word, especially a verb, combines in a sentence:
      ‘‘give’ has a valency of three in ‘I (1) gave it (2) to him (3)’’
      • ‘The purpose of this paper is to study the factors involved in the changing valency of the reflexes of ABHORRERE / ABHORRESCERE in Castilian, ie aborrir ~ aburrir and aborre cer.’

Origin

Early 17th century: from late Latin valentia power, competence, from valere be well or strong.

Pronunciation:

valency

/ˈveɪl(ə)nsi/