fixity

Definitions of fixity
1

n the quality of being fixed in place as by some firm attachment

Synonyms:
fastness, fixedness, fixture, secureness
Antonyms:
looseness
the quality of movability by virtue of being free from attachment or other restraints
Types:
lodgement, lodging, lodgment
the state or quality of being lodged or fixed even temporarily
Type of:
immovability, immovableness
not capable of being moved or rearranged

n the quality of being incapable of mutation

“Darwin challenged the fixity of species”
Synonyms:
immutability, immutableness
Antonyms:
mutability, mutableness
the quality of being capable of mutation
Types:
unalterability
the quality of not being alterable
agelessness
the quality of being timeless and eternal
incurability
incapability of being altered in disposition or habits
Type of:
changelessness, unchangeability, unchangeableness, unchangingness
the quality of being unchangeable; having a marked tendency to remain unchanged