radiusEnglish → FrenchOxford English–Frenchradius /BrE ˈreɪdɪəs , AmE ˈreɪdiəs / noun pl radii or radiuses 1 Mathematics rayon m (of de) 2 (distance) rayon m within a 10 km radius of here dans un rayon de 10 km 3 Anatomy radius m