What is the meaning of -ato?

See -at-

forms nouns from nouns, denoting a status, jurisdiction or period of office; -ate, -dom, -cy, -ship

used with a stem to form the past participle of regular -are verbs

forms adjectives having or resembling the specified thing

a derivative of a specified element or compound; especially a salt or ester of an acid whose name ends in -ico; -ate

-ship; -ate (rank or office)

-age (place)

-ate (derivative of a salt or ester of an acid whose name ends in -ico)

forms an institution from a noun stem

forms the corresponding action of a noun

indicates a baby of a specific animal

forms adjectives of quality

denotes the office of a noun stem

Forms nouns from adverbs, adverbial verb forms, and postpositions, typically with the sense of ‘one that (is) …’, ‘one that has the quality of …’.

Forms the plural of the recent past imperfective tense when the arguments of the verb are first- or second-person.

Source: wiktionary.org

See also