In short

Portuguese lets you change the size and, above all, the feeling of a word by adding a suffix. A gato becomes a gatinho (a small or dear cat), a casa becomes a casarão (a huge house), and bonito becomes bonitíssimo (“extremely beautiful”). None of this is optional decoration: the affectionate diminutive in -inho is one of the clearest markers of natural European Portuguese, and -íssimo is the everyday way to say “very, very”. Get the two spelling reflexes right - the -inho vs -zinho choice, and the c/g shift before the ending - and you will sound far more idiomatic.

The rule

The diminutive: -inho / -inha

The diminutive suffix agrees in gender and number with the noun, exactly like an adjective ending: gato -> gatinho, gata -> gatinha, livros -> livrinhos, casas -> casinhas. There are two shapes of the suffix, -inho and -zinho, and choosing between them is the whole skill.

Choosing -inho or -zinho

• If the word ends in an unstressed -a, -o or -e, drop that final vowel and add -inho/-inha: casa -> casinha, gato -> gatinho, pente -> pentinho, livro -> livrinho.
• Otherwise - a consonant, a nasal, a stressed vowel or a diphthong - keep the whole word and add -zinho/-zinha: flor -> florzinha, animal -> animalzinho, café -> cafezinho, mãe -> mãezinha, cão -> cãozinho, pão -> pãozinho.
• A final -m becomes -n before -zinho: homem -> homenzinho, jardim -> jardinzinho.

Watch the c/g spelling reflex from the reading & pronunciation guide: a stem-final hard c or g becomes qu/gu to keep its sound - pouco -> pouquinho, fresco -> fresquinho, branco -> branquinho.

What the diminutive really does

Size is only half of it. The -inho suffix mostly conveys affection, warmth or softening: um cafezinho is an inviting little coffee, obrigadinho/obrigadinha is a warm thank-you, and Espera um bocadinho (“wait a little bit”) is gentler than Espera um bocado. It attaches happily to adverbs and adjectives too - devagarinho (nice and slowly), quentinho (nice and warm), cedinho (good and early), juntinhos (all cosily together). Some of these have frozen into ordinary words: sozinho (“alone”, from só) is now the normal adjective, not a “little bit alone”.

The augmentative: -ão (and -aço/-aça)

The augmentative -ão means big, often with an admiring or a rough edge: casa -> casarão (a mansion), carro -> carrão (a big flashy car), homem -> homenzarrão (a huge man). Note that -ão usually makes the word masculine, even from a feminine base - a casa but o casarão, a sala but o salão. Many -ão forms have lexicalized into independent nouns: portão (gate, not “big door”), cartão (card), salão (hall). A second suffix, -aço/-aça, adds an intensive or admiring note: um golaço (a stunning goal), um jogaço (a cracking match).

The synthetic superlative: -íssimo

Alongside the analytic superlative from Lesson 18 (muito caro, o mais caro de todos), Portuguese has a one-word absolute superlative in -íssimo, meaning “extremely / very very”: drop the adjective’s final vowel and add -íssimo/-íssima (agreeing in gender and number). caro -> caríssimo, bonito -> bonitíssimo, feliz -> felicíssimo (z becomes c). The same c/g reflex applies: rico -> riquíssimo, longo -> longuíssimo. A handful take the erudite ending -ílimo or are outright irregular, and those are the ones to memorise.

Forms & patterns

Diminutive suffix choice:

Diminutive plurals - the -zinho type pluralizes the base first, then adds -zinhos:

The absolute superlative -íssimo, regular and irregular:

Examples

Common mistakes

• florinha -> florzinha - a word ending in a consonant takes -zinho/-zinha, never a bare -inho (likewise stressed vowels, nasals and diphthongs: café -> cafezinho, cão -> cãozinho).
• pãozinhos -> pãezinhos - for the -zinho plural, pluralize the base first (pão -> pães) and then add -zinhos; you cannot just tack an -s on the end.
• ricíssimo -> riquíssimo - keep the hard sound: c becomes qu before -íssimo (and g becomes gu: longo -> longuíssimo).
• fácil / difícil: the erudite superlative is facílimo / dificílimo - the form the references list first and careful writing prefers; facilíssimo / dificilíssimo also occur and are accepted, just less standard.
• muito bonitíssimo -> bonitíssimo (or muito bonito) - -íssimo already means “very”, so do not pile muito on top of it.
• um gatinha -> uma gatinha, duas casinha -> duas casinhas - the diminutive still agrees in gender and number with its noun.
• cafézinho -> cafezinho - the base loses its written accent when the stress moves onto the suffix (café -> cafezinho, avó -> avozinha).

Tips

• Quick suffix test: ends in an unstressed -a/-o/-e? Drop it and add -inho/-inha (gato -> gatinho). Anything else - consonant, nasal, stressed vowel, diphthong - takes -zinho/-zinha (flor -> florzinha).
• Reach for the diminutive to sound friendly, not to say “small”: um instantinho, agorinha, só um bocadinho soften a request, and obrigadinho/obrigadinha warms a thank-you. It sounds childish in formal writing, so keep it for speech.
• The c/g spelling shift shows up in both suffixes: pouco -> pouquinho, fresco -> fresquinho, rico -> riquíssimo, longo -> longuíssimo. Same rule, two places.
• Treat frozen forms as plain vocabulary: portão, cartão, salão and sozinho are dictionary words now, not live augmentatives or diminutives.
• In everyday EP speech, super + adjective (superbonito, superfixe) competes with -íssimo; recognise and use -íssimo, but know it reads as emphatic or slightly formal.
• In Brazil: the diminutive is, if anything, even more constant in speech (rapidinho, pertinho, tchauzinho), and the machinery is identical - so everything here carries straight over.