precatory

As adjectives the difference between precatory and mandatory

is that precatory is expressing a wish while mandatory is obligatory; required or commanded by authority.

As a noun mandatory is

a person, organisation or state who receives a mandate; a mandatary.

As adjectives the difference between predatory and precatory

is that predatory is of, or relating to a predator while precatory is expressing a wish.

As adjectives the difference between prefatory and precatory

is that prefatory is introductory, preliminary, serving as a prelude or preface while precatory is expressing a wish.