un ‧ chart ‧ ed AC /ʌnˈtʃɑːtəd, ʌnˈtʃɑːtɪd $ -ɑːr-/ BrE AmE adjective
1 . uncharted waters/territory/area etc a situation or activity that you have never experienced or tried before:
This new project will take us into uncharted territory.
2 . not marked on any maps:
an uncharted island