1. (noun) the ambiguous region between two categories or states or conditions (usually containing some features of both)

• twilight zone

1. (noun) an unoccupied area between the front lines of opposing armies

• area
• country

2. (noun) land that is unowned and uninhabited (and usually undesirable)

• land

3. (noun) the ambiguous region between two categories or states or conditions (usually containing some features of both)

• ambiguity
• equivocalness