Czech phonology
This article discusses the phonological system of the Czech language.
The following chart shows a complete list of the consonant phonemes of Czech:
1 The phoneme /r̝/, written ⟨ř⟩, is a raised alveolar non-sonorant trill. Its rarity makes it difficult to produce for foreign learners of Czech, who may pronounce it as [rʒ]; however, it contrasts with /rʒ/ in words like ržát [rʒaːt] ('to neigh'), which is pronounced differently from řád [r̝aːt] ('order'). The basic realization of this phoneme is voiced, but it is voiceless [r̝̊] when preceded or followed by a voiceless consonant or at the end of a word.
/t/ and /d/ can be pronounced as dental stops.
The voiceless realization of the phoneme /ɦ/ is velar [x].
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:
In the standard pronunciation, the glottal stop is never inserted between two vowels in words of foreign origin, e.g. in the word koala.
The phoneme /ɡ/, and the affricates /d͡z/ and /d͡ʒ/ occur in words of foreign origin or dialects only. (However, [ɡ] may also occur as a result of voicing assimilation of /k/, see "assimilation of voice" below.) Phonetically, the affricates can occur at morpheme boundaries (see consonant merging below).
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