How can I repair damaged gloss of hardwood floor due to spilled scented oil?
It would be helpful to know what the floor was finished with. If it was factory finished, it was probably a lacquer finish. If it was a stick built hardwood and finished after install, it is probably urethane.  Regardless, if you gently sand the edges around the damaged area, you should be able to brush in some gloss oil based urethane.  Feather it out very thinly into the existing good finish.  It may not be perfect, but should come close.