- -aõ (obsolete)
- 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
- (slang) forms nouns, from a numeral X divisible by ten and greater than thirty, meaning “someone in his Xs”
- (Brazil, slang) forms nouns, from a numeral X, meaning “X amount of money” or “a bill worth X”
- (somewhat informal) forms the augmentative of adjectives, roughly equivalent to English quite
- forms nouns, from a verb X, meaning a strong or violent instance of doing X
- (no longer productive) forms adjectives, from nouns and proper nouns referring to a location or type of location, meaning “of or pertaining to that location” and nouns meaning “someone from that location”
- forms the third-person plural future indicative, from the infinitive of verbs
- Obsolete form of -am.
Some words ending in -ão pluralise as -ães. However, in these cases the -ão is not a suffix and derives from Old Portuguese -an, from Latin -ānem.