Synonyms of twilight zone

1. twilight zone, ocean floor, sea floor, ocean bottom, seabed, sea bottom, Davy Jones's locker, Davy Jones: usage: the lowest level of the ocean to which light can reach
2. twilight zone, no man's land, ambiguity, equivocalness: usage: the ambiguous region between two categories or states or conditions (usually containing some features of both); "but there is still a twilight zone, the tantalizing occurrences that are probably noise but might possibly be a signal"; "in the twilight zone between humor and vulgarity"; "in that no man's land between negotiation and aggression"