The Collaborative International Dictionary of English v.0.48:

Valency \Val"en*cy\, n.; pl. Valencies. (Chem.)
   (a) See Valence.
   (b) A unit of combining power; a so-called bond of affinity.
       [1913 Webster]

WordNet (r) 3.0 (2006):

valency
    n 1: the phenomenon of forming chemical bonds
    2: (biology) a relative capacity to unite or react or interact
       as with antigens or a biological substrate [syn: valence,
       valency]
    3: (chemistry) a property of atoms or radicals; their combining
       power given in terms of the number of hydrogen atoms (or the
       equivalent) [syn: valence, valency]

The Free On-line Dictionary of Computing (30 December 2018):

degree
valency

   The degree (or valency) of a node in a graph is the number of
   edges joined to it.