Pronunciation: accents on hiatuses

A hiatus occurs in a word with two consecutive vowels pronounced separately in two different syllables.

(Two vowels found in the same syllable are called diphthongs, see Pronunciation: accents on diphthongs.)

It's important to understand hiatuses and diphthongs in order to determine how many syllables are in a word and follow the general rules for Spanish accentuation (i.e., where to pronounce the stress on a word).

Strong and Weak Vowels

In Spanish, vowels are defined as strong or weak:

  • strong vowels: a / e / o
  • weak vowels: i / u

There are different types of hiatus, depending on the vowel combination:

1. Strong + strong (a, e, o + a, e, o)

maestroteacher

ma - es - tro

poemapoem

po - e - ma

As the stress in these words is on the penultimate syllable (-es-, -e-) and the words end in a vowel (-o, -a), there is no written accent, in accordance with the general rules for Spanish accentuation.

reoaerial

This word has four syllables: a - é - re - o

It contains two hiatuses (a+e and e+o). As the stress is on the antepenultimate syllable, this word requires a written accent.

The letter H

The letter "h" is silent and does not affect the hiatus. For example:

ahoranow
a - ho -ra

2. Two of the same vowel (strong or weak)

The same vowel repeated side by side forms a hiatus and again follows the general rules of Spanish accentuation. Here are some examples:

cooperarto cooperate

Créeme.Believe me.

Léeselo.Read it to him.

3.Tonic weak vowel + non-tonic strong vowel
     or
Non-tonic strong vowel + tonic weak vowel

The tonic vowel is the stressed vowel, while the atonic or non-tonic vowel is unstressed. These vowel combinations form a hiatus, separating the vowels into different syllables.

It is important to note that these words, with this specific type of hiatus, always require a written accent if the stress is on the weak tonic vowel. This type of hiatus does not follow the normal accentuation rules.

For example, in the word "grúa", [grú-a] the tonic vowel is the weak vowel "u":

la grúacrane

The word "reúnen" [ re-ú-nen] also has a weak tonic vowel "u" forming a hiatus with -e (eu), and therefore requires the written accent.

Ellos se reúnen.They get together.

Here are more examples of words with this vowel combination that form hiatuses. They all need an accent in order to separate the vowels:

Río, frío, había, tenía, libreríaRiver, cold, there was, he had, bookshop

Rr, frr, bl, mz, ps, mllaTo laugh, to fry, trunk, corn, country, it meows

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Examples and resources

ahoranow
Léeselo.Read it to him.
reoaerial
cooperarto cooperate
Créeme.Believe me.
Río, frío, había, tenía, libreríaRiver, cold, there was, he had, bookshop
poemapoem
Ellos se reúnen.They get together.
Rr, frr, bl, mz, ps, mllaTo laugh, to fry, trunk, corn, country, it meows
la grúacrane
maestroteacher
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