'Fixity' definitions:

Definition of 'fixity'

From: WordNet
noun
The quality of being fixed in place as by some firm attachment [syn: fastness, fixedness, fixity, fixture, secureness] [ant: looseness]
noun
The quality of being incapable of mutation; "Darwin challenged the fixity of species" [syn: immutability, immutableness, fixity] [ant: mutability, mutableness]

Definition of 'Fixity'

From: GCIDE
  • Fixity \Fix"i*ty\ (-[i^]*t[y^]), n. [Cf. F. fixit['e].]
  • 1. Fixedness; as, fixity of tenure; also, that which is fixed. [1913 Webster]
  • 2. Coherence of parts. --Sir I. Newton. [1913 Webster]