A rare or non-standard form possibly conflating casus with casuistry; unclear usage without clear definition in standard dictionaries.
Potentially a confusion or blend of casus and casuistry, though this term does not appear in standard modern English dictionaries.
This word appears to be either a historical variant or possibly a ghost word—a term that entered some dictionaries by mistake and then got copied into others, a phenomenon more common than people realize.
Complete word intelligence in one call. Free tier — 50 lookups/day.