Shawnessy \sha(w)-nessy, shawn(es)-sy\ as a girl's name is a variant of Shawnacy (Gaelic). See for meaning of Shawnessy.
The baby name Shawnessy sounds like Shanessa, Shanisse, Shaneese, Shanese and Shaughnessy. Other similar baby names are Shawney, Shaney, Shanelly, Shawntay, Shawnette, Shawneen and Shawnee.