iron curtain
‘the name of a fire-protection device to be used in theaters, a literal iron curtain’
Lexical development traced from the Tamil root:
M.E. iron < O.E. iren variant (with rhotacism of -s-) of isen < Proto-G. isarn < Ce. isarnon + curtain < is-(e)ro ‘powerful, holy’ < ai < eis < Tamil irumpu