Relating to, or of the nature of, dedication; that has the attribute of dedicating, serving to dedicate. Used chiefly of literary dedication, as in…

= epistolary, adj. (in various senses).

Sacredly, solemnly, or formally devoted; wholly given up, etc.; inscribed (as a book).

Of, relating to, or designating a letter of dedication occurring as a preface to a literary work (see epistle, n. 1c).