no-man's-land
noun uk/ˈnəʊ.mænz.lænd/ us/ˈnoʊ.mænz.lænd/
[ S or U ]（尤指战时两国交界处的）无人地带，真空地带
an area or strip of land that no one owns or controls, such as a strip of land between two countries' borders, especially in a war
to be lost/stranded/stuck in no-man's-land 迷失在／滞留在／困在无人地带
They found themselves trapped in the no-man's-land between the two warring factions. 他们发现自己困在交战双方之间的真空地带。
[ S ]性质尚未确定的形势（或领域），真空地带
a situation or area of activity where there are no rules, or that no one understands or controls because it belongs neither to one type nor another
The families of people who die in custody are in a legal no-man's-land when they try to discover what went wrong. 被监禁人在监禁期间死亡，其家属试图查清事实真相时，却找不到相关的法律支持。