"This American Life" host Glass (3)
I believe the answer is:
ira
'this american life host glass' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ira that I've seen before include "Songwriter George's elder brother" , "terrorists" , "Militant republicans" , "Brother of George Gershwin" , "Illegal organisation, initially" .)