preamble
Preamble (noun) means an introductory statement placed at the start of a document, law or constitution that explains its purpose and the reasoning behind it. Example: “The Preamble to the US Constitution begins "We the People".”
How to use preamble
Learner’s notesIn plain EnglishThe bit at the beginning that explains what is coming and why.
Neutral. The legal-document sense is formal; "without preamble" is a common set phrase in ordinary writing.
Fill the gap
Can you complete this real example?
The _____ to the US Constitution begins "We the People".
Etymology
From Latin praeambulus "walking in front", from prae- "before" + ambulare "to walk", reaching English through Old French preambule.