[{"Bold_text": "noun", "List Items": ["Also called plumb bob plumb bob.a piece of lead or some other weight attached to a line, used for determining perpendicularity, for sounding, etc.; the bob of a plumb line.", "something that weighs down or depresses."]}, {"Bold_text": "verb (used without object)", "List Items": ["to plunge.Synonyms: swoop , drop , dive , fall"]}]