The hyphen and line-breaking

The hyphen (‹-›) leads two quite distinct lives in Portuguese spelling. On the one hand it is a fixed sign belonging to the spelling of certain words — it joins the elements of a compound, links a prefix to its base, and binds clitic pronouns to the verb. On the other it is a provisional sign, used only to split a word at the end of a line — translineação, line-breaking. The 1990 Orthographic Agreement reformed chiefly the first of these, simplifying rules that had previously differed between Portugal and Brazil.

The hyphen in compounds

A hyphen joins the elements of many compounds in which each part keeps its own identity — nouns, adjectives and fixed expressions:

The Agreement removed the hyphen from some very common phrases, now written without it: fim de semana (“weekend”), cor de laranja (“orange-coloured”), cão de guarda (“guard dog”). It kept the hyphen, however, in the names of botanical and zoological species (couve-flor, bem-te-vi) and in compounds whose first element has lost its transparency.

The hyphen in prefixation

This is where most of the doubts lie. The Agreement’s general rule turns on the letter that ends the prefix and the letter that begins the second element.

A hyphen is used when:

• the second element begins with h: anti-higiénico, pré-história, super-homem;
• the prefix ends in the same vowel with which the second element begins: anti-ibérico, contra-almirante, micro-ondas, auto-observação;
• the prefix ends in the same consonant with which the second element begins: inter-regional, hiper-requintado, sub-bibliotecário;
• the prefix is stressed and ends in a stressed vowel — pré-, pró-, pós- — or is one of ex-, vice-, sota-, soto-, circum- and pan-: pós-graduação, ex-marido, vice-reitor, pan-africano.

No hyphen is used — and the elements are written together — when:

• the prefix ends in a vowel and the second element begins with a different vowel: autoestrada, antiaéreo, extraescolar, aeroespacial;
• the prefix ends in a vowel and the second element begins with r or s: here the consonant is doubled: antirreligioso, antissocial, contrarregra, ultrassom, minissaia;
• the prefix ends in a consonant and the second element begins with a vowel: hiperativo, interestadual, superinteressante.

Situation	With hyphen	Without hyphen
same vowel + same vowel	*micro-ondas*	—
vowel + different vowel	—	*autoestrada*
vowel + *r*/*s*	—	*antirreligioso* (rr)
same consonant + same consonant	*inter-regional*	—
consonant + vowel	—	*hiperativo*
anything + *h*	*super-homem*	—

The hyphen with clitic pronouns

The hyphen also links unstressed pronouns (me, te, o, lhe, nos…) to the verb, both in enclisis (pronoun after the verb) and in mesoclisis (pronoun inside the future and conditional):

Note that mesoclisis can produce two hyphens in a single form — dar-to-ia, far-se-á — because both the pronoun and the ending attach to the stem.

Line-breaking

Translineação is the splitting of a word across two lines, marked by a hyphen at the end of the first. It normally follows syllable division, with a few conventions of its own:

• the digraphs that stand for a single sound — lh, nh, ch, gu, qu — are not split: ma-lha, u-nha, que-ro;
• by contrast, the digraphs rr, ss, sc, sç and xc are split, their letters going to different syllables: car-ro, pas-so, nas-cer, des-ço, ex-ce-to;
• a cluster of consonant + l or r pronounced in a single syllable is not divided: re-gra, du-plo; but clusters that cannot begin a syllable in Portuguese are split: ap-to, rit-mo, op-ção, sub-li-nhar.

It is also best to avoid leaving a single letter stranded at the end or start of a line (á-gua, idei-a): though syllabically correct, this is discouraged for the sake of legibility. Line-breaking is, in the end, a matter of readability — unlike the orthographic hyphen, which is part of the word itself.