Lethargy when running around India for a great distance (5,4)
I believe the answer is:
light year
'great distance' is the definition.
'light year' can be an answer for 'distance' (I've seen this before). I'm not certain of the 'great' bit.
'lethargy when running around india' is the wordplay.
'when running' indicates anagramming the letters.
'around' indicates putting letters inside.
'india' becomes 'i' (phonetic alphabet: alpha, bravo, charlie etc.).
'lethargy' is an anagram of 'lghtyear'.
'lghtyear' enclosing 'i' is 'LIGHT-YEAR'.
'for a' acts as a link.
Can you help me to learn more?
(Other definitions for light year that I've seen before include "Astronomical unit of distance" , "such a long way to travel" , "that is way beyond anyone's reach!" , "About six million million miles per annum" , "Nearly 6 million million miles" .)