• -aõ (obsolete)
• -zão (especially after words stressed on the last syllable)

From Old Galician-Portuguese -on, from Latin -ōnem. Akin to Spanish -ón, Italian -one and French -on, compare Romanian -oi.

• Rhymes: -ɐ̃w̃

-ão m (noun-forming suffix, plural -ões, feminine -ona, feminine plural -onas)

1. forms the augmentative of nouns

   Synonyms: -ácio, -aço, -alhão, -arrão, -ázio, -eirão

   Antonyms: -inho, -ito, -culo, -ete

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

      ‎livro (“book”) + ‎-ão → ‎livrão (“big book”)

      ‎janela (“window”) + ‎-ão → ‎janelona (“big window”)

   2. used to refer to things affectionately

      ‎filho (“son”) + ‎-ão → ‎filhão (“used by a father to address his son, when he is proud of the son”)

      ‎amigo (“friend”) + ‎-ão → ‎amigão (“a good friend; a true friend”)

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

      ‎carro (“car”) + ‎-ão → ‎carrão (“high-performance car”)

      ‎calor (“heat”) + ‎-ão → ‎calorão (“intense heat”)

      ‎soco (“punch”) + ‎-ão → ‎socão (“powerful punch”)

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

      ‎cabeludo (“long-haired (adjective); long-haired person (noun)”) + ‎-ão → ‎cabeludão (“person with very long hair”)

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

   ‎abelha (“bee (any sex)”) + ‎-ão → ‎abelhão (“drone”)

   ‎cabra (“she-goat”) + ‎-ão → ‎cabrão (“billy goat”)

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

   ‎calça (“pants”) + ‎-ão → ‎calção (“shorts”)

   ‎agulha (“needle”) + ‎-ão → ‎agulhão (“sharp rock on a riverbed”)

   ‎fogo (“fire”) + ‎-ão → ‎fogão (“stove”)

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

   ‎quarenta (“forty”) + ‎-ão → ‎quarentão (“someone in his forties”)

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

   ‎arrastar (“to drag”) + ‎-ão → ‎arrastão (“an instance of violently dragging something”)

   ‎puxar (“to pull”) + ‎-ão → ‎puxão (“a strong or violent pull”)

   ‎pisar (“to step”) + ‎-ão → ‎pisão (“a strong or violent step”)

6. (informal, derogatory) forms nouns, from a verb X, meaning an agent of such verb

   ‎fugir (“to flee”) + ‎-ão → ‎fujão (“someone who flees from something”)

   ‎cagar (“to shit”) + ‎-ão → ‎cagão (“someone who shits upon something, a coward”)

   ‎mijar (“to piss”) + ‎-ão → ‎mijão (“someone who wets themselves”)

   ‎arregar (“to back off”) + ‎-ão → ‎arregão (“someone who backs off from a challenge, a quitter”)

7. (Brazil, slang) forms nouns, from a numeral X, meaning “X amount of money” or “a bill worth X”

   ‎cinco (“five”) + ‎-ão → ‎cincão (“five bucks”)

   ‎mil (“thousand”) + ‎-ão → ‎milzão (“a thousand bucks”)

-ão (adjective-forming suffix, feminine -ona, masculine plural -ões, feminine plural -onas)

1. (somewhat informal) forms the augmentative of adjectives, roughly equivalent to English quite

   ‎grande (“big”) + ‎-ão → ‎grandão (“quite big”)

From Old Galician-Portuguese -ão, from Latin -ānus (“-ian”). Doublet of -ano.

• Rhymes: -ɐ̃w̃

-ão m (noun-forming suffix, plural -ãos, feminine -ã, feminine plural -ãs)
-ão (adjective-forming suffix, feminine -ã, masculine plural -ãos, feminine plural -ãs)

2. (no longer productive) 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”

   Synonyms: -ano, -ense

   ‎vila (“village”) + ‎-ão → ‎vilão (“villager”)

   ‎cidade (“city”) + ‎-ão → ‎cidadão (“citizen”)

   ‎Beira (“a region in Portugal”) + ‎-ão → ‎beirão (“relating to Beira”, “someone from Beira”)

• Rhymes: -ɐ̃w̃

-ão m (noun-forming suffix, plural -ões)

1. -on (forming nouns denoting subatomic particles)

   ‎magnete (“magnet”) + ‎-ão → ‎magnetão (“magneton”)

From Old Galician-Portuguese -an, from an (modern Portuguese: hão) from Latin habent, third-person plural present indicative of habeō (“to have”).

• Rhymes: -ɐ̃w̃

-ão

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

   ‎falar (“to speak”) + ‎-ão → ‎falarão (“(they) will speak”)

   ‎comer (“to eat”) + ‎-ão → ‎comerão (“(they) will eat”)

   ‎sorrir (“to smile”) + ‎-ão → ‎sorrirão (“(they) will smile”)

• IPA^(key): /ɐ̃w̃/ (paroxytone)

-ão

1. Pre-reform spelling (used until 1943 in Brazil and 1911 in Portugal) of -am., now a common misspelling

Words ending in -ão are pluralised differently depending on its origin:

• Those in which the suffix is derived from Latin -ōnem (including all masculine augmentatives), as well as words derived from French words ending in -on, Italian words ending in -one or Spanish words ending in -ón (all from Latin -ōnem as well), are pluralised with -ões.
• Those in which the suffix derives from Latin -ānus (“-ian”), as well as words derived from other Latin words ending in -ānus, such as mão and chão, are pluralised with -ãos.
• Some words ending in -ão pluralise as -ães. In these cases the -ão is either not a suffix and derives from Old Portuguese -an, from Latin -ānem, -anēs, or derived from an -an suffix in Old Gallician-Portuguese which has become assimilated regardless of its derivation.
  • cão (“dog”) → cães (“dogs”), from Latin canem, canēs
  • pão (“bread”) → pães (“breads”), from Latin pānem, pānēs
  • capitão (“captain”) → capitães (“captains”), from Old Galician-Portuguese capitan, from Latin capitāneus
  • alemão (“German”) → alemães (“German(s)”), from Old Galician-Portuguese aleman, from Latin Alemannus
• Some words have non-predictable pluralisations, for example:
  • ancião (“elder”), aldeão (“villager”) and vilão (“villain”) may be pluralised with -ãos, -ões or -ães
  • damão (“hyrax”) → damões (“hyraxes”), from French daman (“hyrax”), from Arabic دَمَان إِسْرَائِيل (damān ʔisrāʔīl).
  • cafetão (“pimp”) → cafetões (“pimps”), from Lunfardo cáften

• -aço