Illative cāsus
Fram Wikipedian
Se illativus oþþe inberunglica cāsus is grammatisc cāsus for namum. His andgiet is "in" swā in "in hūs", and ne swā in "in hūse". In manigum ġeþēodum man brūceþ þone accusativus cāsus oþþe preposition for þissum. Ac Finnisc hæfþ sundorlīċne illativus cāsus.