The average return of listed & trade-able securities in the share-market is called Market portfolio Return.
According to Khan and Jain,” The expected return on a portfolio is the weighted of the expected returns of the securities comprising the portfolio.”
According to I.M. Pandey,” The return of a portfolio is equal to the weighted average of the returns of individuals assets in the portfolio with weights being equal to the proportion of investment in each asset.”
According to L.J. Gitman,” The return on a portfolio is a weighted average of the returns on the individual assets from which it is formed.”