Meaning

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

noun the quality of being incapable of mutation

originEtymology tree English fix Proto-Indo-European *-teh₂ Proto-Indo-European *-ts Proto-Indo-European *-teh₂ts Latin -itāsder. Old French -itebor. Middle English -ite English -ity English fixity From fix + -ity.

Etymology from Wiktionary, CC BY-SA 3.0