It's now Kolkata (8)
I believe the answer is:
calcutta
'it's now kolkata' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for calcutta that I've seen before include "Large city in India" , "Indian city-port noted for Black Hole" , "Old name for West Bengal?s largest city" , "Old name for Indian's largest city" , "Capital of India until 1912 ..." .)