What does it mean by one Dirac measure and two Dirac measure

Question

Recently, I read paper where they write "assume that $\mu_1$ is defined by one Dirac measure and $\mu_2$ is defined by two Dirac measure". I did not understand this point. What does exactly mean by "defined by one Dirac measure and two Dirac measure". I understand Dirac measure as indicator function over a set.