Handbook of Finnish, 2nd edition, section 4 Pronunciation and writing:

Deviations from the phoneme principle: a summary

Deviations in new loanwords

Mainly due to the complicated history of Finnish language spelling standards, there are many deviations from the phoneme principle in relatively new loanwords. Many of the items of the following list are described in more detail in section New loanwords.

Other deviations

Deviations in originally Finnish words and in old loanwords also reflect the history of Finnish language standards, in particular attempts at maintaining regularity in writing. For example, according to general principles of Finnish inflection, the genitive of the word ruoka is ruoan, because consonant gradation just makes the k vanish, when the genitive suffix n is appended. However, in practice the pronunciation has been simplified to ruuan. This means that to preserve regularity in written form of the language, irregularity in the correspondence between spelling and pronunciation has been introduced. Although it is now accepted to write ruuan, this has just created additional complexity, since the “regular” spelling is still allowed and often presented or regarded as more correct.

The main deviations are:

Marking stress

The stress is not a phoneme, but it can be comparable to a phoneme due to making a distinction in meaning. As described in section Stress, the stress cannot always be inferred from the written form of a word. The main reason to this is that compound words are not written systematically so that their structure is indicated.

For example, the spelling tangoilta is used both for a compound word consisting of tango and ilta, with a syllable break between o and i and with secondary stress on the syllable il tán.go.ìl.ta), and for a form (ablative plural) of tango, pronounced as three syllables and without a secondary stress (tán.goil.ta). The same spelling is also used for the ablative plural of tanko and tanga, but these do not differ in pronunciation from the form of tango.

The spelling piilevä may be a form of the verb piillä or (rarely) a compound word consisting of the words pii and levä. The syllable division is the same, but in the latter case, there is a secondary stress, [píilèvä], making the pronunciations different.

Syllable boundaries

Similarly to stress, syllable boundaries are not phonemes but may act like phonemes in the sense of making a difference in both pronunciation and meaning. This happens in non-compound words, too. The spelling hauista can be elative plural of hauki, the partitive singular of hauis, or the elative plural of haku. In the first two cases, the syllable structure is hau.is.ta, but in the third case it is ha.uis.ta, since a syllable break appears in the place of a lost k.

In some loanwords, a combination of a vowel and i does not constitute a diphthong, but this is not indicated in spelling, e.g. ateisti [á.te.ìs.ti], but on the other hand polyteisti [pó.ly.tèis.ti].

According to language rules, a syllable boundary is indicated when it appears between identical vowels. It is indicated with a hyphen if the vowels belong to different parts of a compound, as in linja-auto, and with an apostrophe otherwise, e.g. ruo’on. Moreover, in new loanwords, this principle is not always followed; e.g. kooperaatio, admittedly a rare word, is pronounced [ko.o.pe.raa.ti.o], whereas koordinaatio is pronounced [koor.di.naa.ti.o].

It is allowed to use an apostrophe to indicate syllable boundary otherwise, too, e.g. hau’ista and ha’uista, but this is very rare in modern language.


© 2015, 2025, 2026 Jukka K. Korpela, jukkakk@gmail.com. This book was last updated February 18, 2026.