How old are you? Where did your parents find the name?
Most of the references to males name Nondas seem to indicate it is a Greek name as a male name.
The only reference I could find on short notice to Nondas as a possible Native American name is the following site which mentions a visit in 1791 to a town of the Seneca
nation in what is now Livingston County, New York
, called Nondas, with the claim that Nondas meant "high or steep hill". But with only one reference that has to be a "perhaps" derivation, not a sure one:http://www.telusplanet.net/public/dgarneau/indian18.htm