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.
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