prolocutory
/prəʊˈlɒkjʊt(ə)ri/Now archaic (and historical ) and rare
noun
A prologue, a preface.
adjective
Of, relating to, or characteristic of a prolocutor.
Origin
Late Middle English; earliest use found in Osbern Bokenham (c1393–c1464), poet and Augustinian friar. From post-classical Latin prolocutorius (adjective) preliminary, foregoing from post-classical Latin prolocutor + -ius, suffix forming adjectives; compare -ory.