What is the meaning of -io?

a place, usually a country, named after the root, whether that is a people, person, city, or river

a science named after its practitioner

-ium; used to form the names of chemical elements

Forms nouns from verbs or verbal stems.

Forms nouns from other nouns, adjectives, numbers or their stems.

suffix denoting the country, region, domain, territory or province dependent upon the authority of a person

used with verb roots to derive nouns with durative, intensive or frequentative connotation; -le

alternative form of -ivo

added to nouns and adjectives to form adjectives meaning “having the quality of”; -y

used with verb roots to derive simple deverbal nouns

forms the name of chemical elements; -ium

used with a stem to form the third-person singular past historic of regular -ire verbs

used with a stem to form the simple past of verbs

Used to form abstract nouns from verbs.

forms animate nouns of various meanings, often colloquial or pejorative

1. forms nouns designating a type of person
   1. attached to noun stems, forms nouns referring to a related profession

      forms nouns designating a type of person

      1. attached to noun stems, forms nouns referring to a related profession

         attached to noun stems, forms nouns referring to a related profession

         attached to verb stems, forms agent nouns

         also forms names, especially cognomina.

         attached to noun stems, forms a diminutive or similar derived noun

         Suffixed to noun or adjective stems, forms certain nouns designating things; often described as a kind of diminutive.

         Used to form factitive verbs from adjectives.

         Used to form some irregular third conjugation verbs.

         Used to form fourth conjugation verbs.

         A suffix forming abstract nouns.

         -ive; -y (forms adjectives from verbs, indicating a tendency or inclination)

         forms collectives

         -ium (forms the names of chemical elements and isotopes)

         obsolete spelling of -iu

         -ium

         Forms verbnouns from verbs and other parts of speech.

         Source: wiktionary.org