English

Noun

uncharted water ‎(plural uncharted waters)

1. An area of sea that has not been surveyed, or those the details of which have not been entered on nautical charts
2. (figuratively, by extension) any unknown and potentially dangerous situation.

   1900 That is the rock that he is in danger of, for he is going recklessly over uncharted waters. - Walter Hines Page, Arthur Wilson Page - The World's Work ...: A History of Our Time