Did You Know?
Most things "quadrennial" occur every four years (that's the more common use). We can say, for example, that the U.S. presidential election is a quadrennial event. But we can also say that president's term in office is quadrennial, making good use of the "lasting four years" sense. The Latin combining form "quadri-" adds a factor of four to many English words: "quadriceps" (the thigh muscle, which has four parts), "quadrilateral" (a four-sided polygon), "quadragenarian" (a person in his or her 40s), and "quadricentennial" (a 400th anniversary), to name a few. The "-ennial" part of "quadrennial" has the same root as in "biennial" and "centennial"; all trace back to "annus," the Latin word for "year."