The word "most provisionary" refers to something that is very tentative or temporary in nature. Its antonyms, on the other hand, refer to things that are more permanent or certain. Some antonyms for "most provisionary" include fixed, established, settled, long-lasting, stable, and certain. These words describe something that is reliable and predictable, rather than temporary or subject to change. They convey a sense of permanence and confidence, rather than uncertainty and doubt. Antonyms for "most provisionary" can be useful when you want to emphasize the stability or reliability of a particular situation or object.