No, it is a proper noun. It is the name of a person.
Seems Palau is the name country in the western Pacific Ocean comprising a group of volcanic islands that are part of the Caroline Islands. Capital: Koror Then in what way an adjective is sought for the above name Palau?
Caroline Ingalls' maiden name was Caroline Quiner.
Caroline Cage's birth name is Katalin Csillag.
Caroline Kennedy real name is Caroline Hissenburg
Caroline Benn's birth name is Caroline DeCamp.
Caroline Catz's birth name is Caroline Caplan.
Caroline Rabaliatti's birth name is Caroline Rabaliatti.
Caroline Pocklington's birth name is Caroline A. Pocklington.
Caroline Reid's birth name is Caroline Reid.
Caroline Manzo's birth name is Caroline Laurita.
Caroline Somers's birth name is Caroline Beth Arminio.
Caroline Tresca's birth name is Marie-Caroline Tresca.