1. a new and/or unfamiliar area to someone
in uncharted territory
'Uncharted' is an adjective used to describe something that has never been seen or described before. An 'uncharted place' is an area of land or territory which is not mapped or which has not been surveyed. An 'uncharted territory' also has the same meaning. Going into 'uncharted territory' or 'uncharted waters' also has a figurative meaning - doing something that has not been done before or when the result is uncertain or studying an area that has not been studied previously. These are popular expressions in both social and professional contexts.