Indian is one from Haryana ecologist upset (5)
I believe the answer is:
ocean
'indian is one' is the definition.
(I've seen this in another clue)
'from haryana ecologist upset' is the wordplay.
'from' says the answer is hidden in the clue.
'upset' is a reversal indicator.
'naeco' is hidden in the letters of 'haryana ecologist'.
'naeco' written backwards gives 'OCEAN'.
(Other definitions for ocean that I've seen before include "Pacific, for example" , "Huge expanse" , "Large stretch of water" , "The deep" , "A mighty sea" .)