This paragraph is prelusive because it serves as an introduction to the meaning of this specific word. Things that are prelusive come before something else.
An event, piece of writing, or piece of music is prelusive when it acts as a prelude to something more important or substantial that follows. Both words are derived from the Latin pre-, "before," and ludere, "to play." Introductory speeches before a main speaker takes the stage are prelusive. A small skirmish between two nations might be considered prelusive if it comes before a full-scale war. A rumbling from a mountain volcano might be prelusive to a violent eruption.