Adventist adjective 2noun 2forms 3 adjective2 •Relating to believers in the Second Advent of Jesus; relating to Adventism. •Relating to Seventh-day Adventism / the Seventh-day Adventist Church. noun2 •One who believes in the Second Advent (usually known as the Second Coming) of Jesus; an advocate of Adventism. •A member of the Seventh-day Adventist Church. formsAdventists · more Adventist · most Adventist