  We report the STAR measurements of dielectron ($e^+e^-$) production at
midrapidity ($|y_{ee}|<$1) in Au+Au collisions at $\sqrt{s_{\rm NN}}$ =
200\,GeV. The measurements are evaluated in different invariant mass regions
with a focus on 0.30-0.76 ($\rho$-like), 0.76-0.80 ($\omega$-like), and
0.98-1.05 ($\phi$-like) GeV/$c^{2}$. The spectrum in the $\omega$-like and
$\phi$-like regions can be well described by the hadronic cocktail simulation.
In the $\rho$-like region, however, the vacuum $\rho$ spectral function cannot
describe the shape of the dielectron excess. In this range, an enhancement of
1.77$\pm$0.11(stat.)$\pm$0.24(sys.)$\pm$0.33(cocktail) is determined with
respect to the hadronic cocktail simulation that excludes the $\rho$ meson. The
excess yield in the $\rho$-like region increases with the number of collision
participants faster than the $\omega$ and $\phi$ yields. Theoretical models
with broadened $\rho$ contributions through interactions with constituents in
the hot QCD medium provide a consistent description of the dilepton mass
spectra for the measurement presented here and the earlier data at the Super
Proton Synchrotron energies.
