Usually appended to the genitive or nominative singular stem.
Place names already ending in -la often do not duplicate the suffix, and their adjective forms may be formed with simply -inen (e.g. Karjala → karjalainen, not ˣkarjalalainen).
From compounds with laji(“kind, sort”) + -inen. The origin as a separate word can still be seen in the imperfect accommodation to vowel harmony. The suffix has been reinforced and influenced by the somewhat similar sounding -llinen (e.g. dialectal millinen for millainen).
Combined with the genitive form of an adjective, forms an adjective indicating a smaller degree of the quality than that described by the original adjective.
As this suffix is historically a compound, it is not subject to vowel harmony in the standard language; with the exception of the word yhtäläinen, it always has back vowel harmony. In colloquial use it may have a front vowel variant, if not the speaker has not been explicitly taught to avoid that, which proves the rule moot.
