A "meso" compound is a symmetric RS species, where the 2 (potentially) chiral centres map onto each other upon inversion. Given that R,S = S,R, these are the same structure, and symmetrically equivalent. Of course, the structure could give rise to S,S and R,R enantiomers, as well as an equivalent pair of R,S and S, R. In this case, the former pair, S,S and R,R, ARE enantiomeric.
I urge you to get a set of simple models to demonstrate the isomerism, and also practise representing the isomerism on the printed page.
Start with H_3C-CH(OH)CH(OH)CH_3. This is a simple structure, but will generate a pair of non-superposable enantiomers, and a meso-isomer. I forget its trivial name, but the structure is a favorite for examiners.
