Word of the Week: quotidian (kwō-TĬD-ē-ən) Definition (Adjective) Of an everyday character; commonplace, mundane, ordinary. In Context "These are the solid, obvious, sharply outlined, in-the-way things of quotidian experience: the walls that obstruct, the rain that falls, the projectile that hits, the stone that stubs." Lorraine Daston, Editor, Biographies of Scientific Objects, 2000.