1.NounA collection of miscellaneous notes, remarks, or fragments of writing, typically preserved in a notebook. Originally, a book of accounts, so named from the placing of debt and credit in opposition to each other.
"These adversaria provide a fascinating look into the author's drafting process."
2.NounA collection of notes or commentaries; a commonplace book.
"The museum displayed the scientist's primary adversaria under a protective glass case."