bicoastal UK /baɪˈkəʊstəl/US /baɪˈkoʊstəl/adjective 1noun 1forms 3 adjective1 •Of, pertaining to, or concentrated on two coasts, often specifically the Atlantic and Pacific coasts of North America.Chess, it seems, is even more bicoastal than the usual occasions of midwestern envy. — 1988 noun1 •A person who lives near two coasts.Ms. Zohn said being married bicoastals poses a variety of challenges, not the least of which is explaining their situation. — 2007 formsbicoastals · more bicoastal · most bicoastal