Nessa has never ranked in the top 1000 in the US. She has several different origins. One is the modern Cornish name meaning, “second.” Nessa is also a diminutive form of Agnes, and has become a stand alone name. She can also be considered a nickname of Vanessa, and an anglicised version of the Irish Neasa. 

    There are some great literary references to characters named Nessa. I would love to see her get used more.