fifth columnist

n.

第五纵队队员，间谍；

复数：fifth columnists

Fifth Columnist
Fifth columnist
Fifth columnist
A fifth columnist
The Fifth Columnist
THE FIFTH COLUMNIST
Book Review: God's Fifth Columnist and Other Writings
GOD'S FIFTH COLUMNIST? : A View of Novelist William Gerhardie (1895-1977)
Feminist Theory as Fifth Columnist or Discursive Vanguard? Some Contested Uses of Gender Analysis in Historical Sociology
A World without Privacy: What’s Wrong with Privacy Protections? Provocations from a Fifth Columnist