-itysuffix

The usual form in which the suffix (Latin -tās, -tātem, expressing state or condition) appears, the i- being originally either the stem vowel of the radical (e.g. Latin suāvi-tās suavity), or its weakened representation (e.g. Latin puro-, pūri-tās purity), rarely a mere connective (e.g. Latin auctōr-i-tās authority; so Middle English emperorite, in Vernon MS., St. Ambrose 886). The last became more frequent in medieval and modern Latin, and the modern languages, in abstract nouns from comparatives, as majority, minority, superiority, inferiority, interiority. Hence such formations as egoity, with playful or pedantic nonce-words of English formation, as between-ity, coxcomb-ity, cuppe-ity, table-ity, threadbar-ity, woman-ity (after humani-ty), youthfull-ity. After i, -ity becomes -ety (see -iety suffix). The termination was in Latin often added to another adjectival suffix, e.g. -āci-, -āli-, -āno-, -āri-, -ārio-, -bili-, -eo-, -idi-, -ido-, -ili-, -īli-, -ino-, -īno-, -io-, -īvo-, -ōci-, -ōso-, -ui-, -uo-, etc., whence the English endings -acity, -ality, -anity, -arity, -ariety, -bility, -eity, -idity, -ility, -inity, -iety, -ivity, -ocity, -osity, -uity, some of which, as -bility (-ability, -ibility) attain almost to the rank of independent suffixes. The earlier popular French form was -eté, in English -ety and -ty, as in safety, bounty, plenty: see -ty suffix¹.