preamble

a preliminary introduction to a statute or constitution (usually explaining its purpose)

noun.communication

Source: WordNet 3.0

A introductory portion; an introduction or preface, as to a book, document, etc.; specifically, the introductory part of a statute, which states the reasons and intent of the law.

noun

Source: webster1913

make a preliminary introduction, usually to a formal document

verb.communication

Source: WordNet 3.0

To make a preamble to; to preface; to serve as a preamble.

verb

Source: webster1913