[{"Bold_text": "noun", "List Items": ["a staunch supporter or adherent; one who can be relied upon.", "something upon which one can rely and therefore choose or use regularly.", "something or someone held ready to serve as a substitute, especially a radio or television program used as a filler in case of cancellation of a regularly scheduled program.", "a traveler who is waiting for last-minute accommodations to become available on a plane, train, or other transport as a result of a cancellation."]}, {"Bold_text": "adjective", "List Items": ["kept readily available for use in an emergency, shortage, or the like:a standby player.", "of or relating to last-minute accommodations, the transport that offers them, or a traveler who is waiting for them:a standby flight.", "of or relating to a waiting period."]}]