Contours of the density in the xz-plane (z being the rotation axis) for a prototypical rotating O star with L_* = 10⁶ L_⊙, M_* = 52.5 M_⊙, R_p = 19 R_⊙, and v_rot = 432 km s⁻¹ (corresponding to Ω = 0.9). The density has been scaled by values from the non-rotating model with Ω = 0. While the thick solid line corresponds to the surface of the (distorted) star, the dashed line would correspond to a spherical surface. Additionally, the velocity vectors are displayed.