Contraction.
When two vowels are found together from the loss of a consonant or other causes, they frequently become a long vowel or a diphthong. This phenomenon is called Contraction, and occurs frequently in Finnish. It can, like the loss of final vowels, be easily accounted for on phonetic grounds, if it be remembered that the tonic accent of a word is always on the first syllable, so that there is a natural tendency to drop or pronounce quickly syllables at the end of words.
This contraction is of two kinds:—
48. I. The first kind takes place when the vowels of the two final syllables of a word are the same, and the consonant between them (h in nouns or t in verbs) falls out. Thus, vierahan becomes viera͡an (two syllables); lupatan, lupa͡an; tervehen, terve͡en.
This form of contraction is universally employed in certain classes of nouns and verbs, the uncontracted forms being only found in poetry and the Karelian dialect.
49. II. The second kind is when the vowels of the last and penultimate syllables of a word meet, the last vowel being a or ä. Under these circumstances the assimilation of the second vowel to the first, and contraction of the two into one long vowel is admissible, but not obligatory, though it usually takes place if the first vowel is o, e, or ö. Thus lankean (I fall), kokoan (I collect), become lankeen, kokoon. But the contraction of ia or ua to ii, uu is rare.
Forms like silee, ainoo for sileä, ainoa are found in poetry. In prose this form of contraction is confined to verbs.
The contraction of two vowels into one long vowel or diphthong also occurs in adding the case suffixes:—
(1) The a or ä of the partitive sing. with the final vowel of roots ending in a or ä forms a long vowel, e.g. jalka-a, leipä-ä become jalka͡a, leipä͡ä.
(2) When the e of a termination becomes i after the final vowel of a root, this i forms a diphthong with that vowel, e.g. korvaen becomes korva͡in; and when the i of the plural meets with the final vowel of a root it forms a diphthong with it.
The point in all these cases is that, though no change takes place in writing, the two vowels form one syllable instead of two.
Vowels which meet from the disappearance of k are often contracted in pronunciation: te͡en, nä͡in from teken, näkin, are pronounced as one syllable.