In English Panamanian, in Spanish Paname?o.
Panamanian
Panamanian
according to the web page (below) the input from someone who lives there says:
The previous answer provided is absolutely incorrect- I currently live in Panama, and the natives of this country refer to themselves as "Panamenos/nas" (with the n-tilde). Many people also self-identify by their indigenous tribal affiliation, or by the province or region from which they hail. And the country immediately to our east/south is "Colombia", not "Columbia"!
If someone from Canada is Canadian, and someone from America is American, what is someone from Panama??