A preliminary statement, especially the introduction to a formal document that serves to explain its purpose.
An introductory occurrence or fact; a preliminary.
[Middle English, from Old French preambule, from Medieval Latin praeambulum, from neuter of praeambulus, walking in front : prae-, pre- + ambulāre, to walk; see ambulate.] pre·am'bu·lar'y (-byə-lěr'ē) adj.