Czech phonology

This article discusses the phonological system of the Czech language.

Consonants

Consonant chart

The following chart shows a complete list of the consonant phonemes of Czech:
Phonetic notes:

Sibilants are laminal post-alveolars.
The approximant is mainly pronounced apico-alveolar, although a velarized pronunciation without a firm tongue tip contact is not unusual.
Both and are trills though commonly realized with a single contact.
The phoneme, written, is a raised alveolar non-sonorant trill. Its rarity makes it difficult to produce for most foreign learners of Czech, who may pronounce it as ; however, it contrasts with as well as. For example, the words ržát & žrát, are both pronounced differently from řád . The basic realization of this phoneme is voiced, but it is voiceless when preceded or followed by a voiceless consonant or at the end of a word. Phonetically, the sound is a period of friction interrupted at the beginning by a contact or contacts created by a retracted apico-alveolar gesture.
Sonorants, become syllabic between two consonants or after a consonant at the end of a word.
and can be pronounced as dental stops. While is commonly realized as apico-alveolar, is more likely to be laminal denti-alveolar.
and are alveolo-palatal with primarily lamino-alveolar/postalveolar and lateral dorso-palatal contact.
is alveolo-palatal nasal.
The voiceless realization of the phoneme is velar.
Glottal stop

The glottal stop is not a separate phoneme. Its use is optional and it may appear as the onset of an otherwise vowel-initial syllable. The pronunciation with or without the glottal stop does not affect the meaning and is not distinctive.
The glottal stop has two functions in Czech:

The emphasis on the boundaries between words or in compound words is usually inserted between two vowels which do not form a diphthong, e.g. zneužívat , táta a máma ; it is also inserted before initial vowels of the second part of compound words, e.g. trojúhelník . This usage of the glottal stop is usual in Bohemia. Pronunciation without it is typical of Moravian regions, e.g.,. Both variants are regarded as correct.
Certain words can be emphasized by the use of the glottal stop.

In the standard pronunciation, the glottal stop is never inserted between two consecutive vowels without an intervening morpheme boundary, which occurs chiefly in words of foreign origin, e.g. in the word koala.

Marginal consonant phonemes

The phonemes,, and usually occur in words of foreign origin or dialects only. As for /f/, however, the number of words where it occurs is still significant and many of them are commonplace, e.g. fialový, fronta, fotit, doufat. It is also used in common first names and surnames. The phoneme /g/, though rarer than /f/, appears in frequently used words as well, e.g. graf, gram, grep, regulace. The occurrence of is uncommon and typically signals that the word is of English origin, but not always. The phoneme is quite marginal, used mostly by dialects spoken near the border with Slovakia.
Nevertheless, as phonemic realizations , , and all four consonants also occur as allophones of /v/, /k/, /t͡ʃ/ and /t͡s/ respectively due to assimilation of voice. Moreover, affricates can phonetically occur at morpheme boundaries.

Consonants in the script

Other consonants are represented by the same characters as in the IPA.

IPA	Czech alphabet
	š
	ž
	ň
	ť
	ď
	h
	Ch
	c
	č
	dž
	ř

Consonant assimilation

Realizations of consonant phonemes are influenced by their surroundings. The position of phonemes in words can modify their phonetic realizations without a change of the meaning.

Assimilation of the place of articulation

Labiodental is a realization of before labiodental fricatives and, e.g. in the word tramvaj .
Velar is a realization of before velar stops and, e.g. in the word banka .

The former assimilation is optional while the latter is obligatory. Realization of the former as is thus possible, especially in more prestigious registers, whereas realization of the latter as is considered hypercorrect, and hence incorrect.

Assimilation of voice

Assimilation of voice is an important feature of Czech pronunciation. Voiced obstruents are, in certain circumstances, realized voiceless and vice versa. It is not represented in orthography, where more etymological principles are applied. Assimilation of voice applies in these circumstances:

In consonant groups – all obstruents in the group are realized either voiced or voiceless. It is mostly governed by the last consonant in the group, e.g. roztok .
Voiced obstruents are realized voiceless in the pre-pausal position. Compare led – ledu vs. let – letu – the nominative forms of both words are pronounced the same due to final devoicing in the first; but in the other inflection forms their pronunciation differs.

Voiced and voiceless obstruents form pairs in which the assimilation of voice applies :

Voiceless	Voiced

Sonorants have no voiceless counterparts and are never devoiced. They do not cause the voicing of voiceless consonants in standard pronunciation, e.g. sledovat .
There are some exceptions to the rules described above:

The phoneme also does not cause the voicing of preceding voiceless consonants, e.g. světlo . However, followed by a voiceless consonant is also realized voiceless, e.g. vsadit .
The phonemes and form a special voice pair even though the places of articulation differ, e.g. vrh – vrhu . The phoneme followed by a voiced obstruent can be realized as either or, e.g. abych byl . The phoneme undergoes progressive assimilation after /s/ in Bohemian pronunciation, e.g. na shledanou , whereas standard regressive assimilations are typical of Moravian pronunciation,.
The phoneme does not cause assimilations of adjacent consonants, but it undergoes progressive as well as regressive assimilation according to its surroundings, e.g. při . Its basic realization is voiced. In final position, it is voiceless.
Consonant merging

Two identical consonant phonemes can meet in morpheme boundaries during word formation. In many cases, especially in suffixes, two identical consonant sounds merge into one sound in pronunciation, e.g. cenný , měkký .
In prefixes and composite words, lengthened or doubled pronunciation is obvious. It is necessary in cases of different words: nejjasnější vs. nejasnější . Doubled pronunciation is perceived as hypercorrect in cases like or.
Combinations of stops and fricatives usually produce affricates : dětský . Both phonemes are pronounced separately in careful pronunciation:.

Vowels

There are 10 monophthongal and 3 diphthongal vowel phonemes in Czech:. Czech is a quantity language: it differentiates five vowel qualities that occur as both phonologically short and long. The short and long counterparts generally do not differ in their quality, although long vowels may be more peripheral than short vowels.
As for the high front vowel pair, there are dialectal differences with respect to phonetic realisation of the contrast: in the Bohemian variety of Czech, the two vowels are differentiated by both quality and duration, while in the Eastern Moravian variety of Czech the primary difference is that of duration. Therefore, in the Bohemian variety, the transcription more accurately reflects the tradeoff between the qualitative and the durational difference in these vowels, while in the Eastern Moravian variety of Czech, the transcription captures the primary durational difference.
Besides length, Czech differentiates three degrees of height and three degrees of backness.
Vowel length and quality is independent of the stress.
Image:Czech vowel chart.png|right|thumb|upright=1.59|Czech vowel chart, based on

Short vowels

Long vowels

Long vowels are indicated by an acute accent or a ring.

Diphthongs

The phonemes and are sometimes transcribed and. This transcription describes the pronunciation in Central Bohemia and Prague, which is more open. The standard pronunciation is something between and, i.e. mid back vowel.
The letter ě is not a separate vowel. It denotes after a palatal stop or palatal nasal, after /m/, and after other labial consonants.
The vowel sequences ia, ie, ii, io, and iu in foreign words are not diphthongs. They are pronounced with an epenthetic between the vowels:.

Prosody

Stress

The stress is nearly always fixed to the first syllable of a word. Exceptions:

One-syllable prepositions usually form a unit with following words. Therefore, the stress moves to the prepositions, ˈPraha → ˈdo Prahy. This rule is not always applied in words which have four or more syllables: e.g. either ˈna koloˌnádě or na ˈkoloˌnádě are possible.
Some one-syllable words, ti, to, se, si, jsem, jsi are clitics — they are not stressed and form a unit with preceding words, therefore they cannot be the first words in sentences. Example: ˈNapsal jsem ti ten ˈdopis.

Long words can have the secondary stress which is mostly placed on every odd syllable, e.g. ˈnej.krás.ˌněj.ší. However, in some cases it can be placed on the fourth syllable, e.g. ˈnej.ze.le.ˌněj.ší.
The stress has no lexical or phonological function; it denotes boundaries between words but does not distinguish word meanings. It has also no influence on the quality or quantity of vowels, i.e. the vowels are not reduced in unstressed syllables and can be both short and long regardless of the stress. Thus, the Czech rhythm can be considered as isosyllabic.