Among the characteristic features of the Finnish language is the use of
numerous derivational affixes and diverse word-formation options.
Although Finnish has very old derivational elements, fairly recent
suffixes and even completely new ways of forming words are also found.
It is typical of word-formation options that they change, and that their
frequency and popularity varies over time. In this diachronic study,
the focus is on one of the most recent suffixes used in the Finnish
language, the agentive -Ari suffix (e.g. kaahari ‘reckless driver’, kuohari ‘gelder of animals’). What makes the -Ari
derivatives special is that the type has been adopted on the model of
words borrowed from the Germanic languages. Historically these are
descended from the Latin derivational element -ārius,
which was adopted widely in the European languages. The main purpose of
the present study was to find out whether, from a diachronic
perspective, the -Ari-derived agent nouns
actually represent an independent derived semantic category in Finnish.
Another purpose was to characterize the process whereby the -Ari
suffix was adopted in Finnish: at what point do these derived forms
actually first occur in Finnish, and how has the use of the derivational
element been manifested at different times. A final significant task of
the study was to clarify the potential reasons and motivations for this
morphological borrowing.