a resonant element including : a vibrating body vibratable in orthogonal x - and z - directions ; exciting means for causing the vibrating body to be subjected to an excitation vibration in the x - direction ; excitation deflection detecting means for detecting the deflection of the vibrating body in the z - direction during the excitation vibration thereof in the x - direction ; and excitation deflection inhibiting means for inhibiting the deflection of the vibrating body in the z - direction .