  We propose a chiral charge (electric toroidal monopole) as the hidden order
parameter in URu$_{2}$Si$_{2}$, which satisfies all the symmetry conditions
accumulated by many experimental and theoretical efforts since its discovery.
By using the minimal effective $d$-$f$ hybridized model in the itinerant
picture, we demonstrate expected cross-correlated phenomena under the chiral
charge ordering, and spatial distribution of the order parameter with surface
or domain boundary. Based on the results, we discuss possible experiments by
using NQR and diffraction measurements under an electric field, or optical
measurements near the surface or domain boundary, although the proposed fully
rotational symmetric order parameter is hard to detect as it is.
