What is the meaning of -ão?

forms the augmentative of nouns

forms nouns, from nouns denoting things, meaning “big thing,” usually but not necessarily with the same gender

used to refer to things affectionately

forms nouns, from nouns, implying that the suffixed noun is powerful or good

in nouns that are formed from, or homonymous with, an adjective, it augments the quality expressed by the adjective

forms the masculine of animal names (whether the animal refers to females or to males and females)

forms nouns, from nouns, denoting an item of the same class as the suffixed noun, or which shares a characteristic with the suffixed noun

forms nouns, from a numeral X divisible by ten and greater than thirty, meaning “someone in his Xs”

forms nouns, from a verb X, meaning a strong or violent instance of doing X

forms nouns, from a verb X, meaning an agent of such verb

forms nouns, from a numeral X, meaning “X amount of money” or “a bill worth X”

forms the augmentative of adjectives, roughly equivalent to English quite

forms adjectives, nouns and proper nouns referring to a location or type of location, meaning “of or relating to that location” and nouns meaning “someone from that location”

-on (forming nouns denoting subatomic particles)

forms the third-person plural future indicative, from the infinitive of verbs

Pre-reform spelling (until Brazil 1943/Portugal 1911) of -am. , now a common misspelling

Source: wiktionary.org