Synonyms for Fixedness (same or very similar meaning)
WordNet sense 1 (remaining in place):
immobility, stationariness
WordNet sense 2 (the quality of being fixed in place as by some firm attachment):
fastness, fixity, fixture, secureness
WordNet sense 3 (the quality of being fixed and unchangeable):
unalterability
From the ODE community, based on WordNet
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