Breathless Hindus running for many miles (5)
I believe the answer is:
indus
'for many miles' is the definition.
I can't judge whether this defines the answer.
'breathless hindus running' is the wordplay.
'INDUS' is hidden within the letters.
However, I am uncertain how this is indicated.
Can you help me to learn more?
(Other definitions for indus that I've seen before include "Punjab river" , "Sacred flower" , "Asian runner" , "Long river of Asia" , "River of India and Pakistan" .)