In linguistics, the excessive case indicates a transformation away from a state. This case completes the "going in, being in, going out" paradigm:
- translative - transform into a state. "Appointed a minister", nimitettiin ministeriksi.
- essive - existence in a state. "Stays a minister", pysyy ministerinä.
- excessive - transform away from a state. "Fired from the minister's job", sai potkut ministerintä.
Observe the similarity to the
illative,
inessive and
elative cases (into, in, out from the inside something) for physical locations. This is an actual "hole in our thinking" we're unaware of. Notice how the state - "job" - has to explicitly stated; "fired from a minister" is incorrect.
Only some Eastern dialects of Finnish, like Karelian and Savo, use this case. Its case ending is -nta/ntä depending on vowel harmony. Because its use is so limited geographically, it has not entered standard Finnish. Speakers from other areas will not recognize it. The origin of the ending may be explained as -na + -ta → -nta, where the essive "in a role" is prefixed with an ablative "from", creating the concept "from a role". Notice that the old Finnish ablative -ta has been transformed into a partitive, its role overtaken by the modern Finnish ablative -lta.
For example, huollettava "dependant" → Kuol (pois) huollettavanta "Died (away) from being a dependant". This cannot really be expressed other than in an analytic fashion, i.e. "Died, and is no longer a dependant", in standard Finnish or English. As a case, it's added to the adjectives, and it works with the translative case in the most logically beautiful way: Hyväntä ystäväntä muuttui hän pahimmaksi vihamieheksi. "From being a good friend, he changed into a worst enemy."
Source: http://www.kotus.fi/julkaisut/ikkunat/2003/kielii2003_7.shtml