Write about “the greatest” Gurkha? (6)
I believe the answer is:
nepali
'gurkha?' is the definition.
(gurkha is a kind of Nepali)
'write about the greatest' is the wordplay.
'write' becomes 'pen' (synonyms).
'about' is a reversal indicator.
'the greatest' becomes 'Ali' (Muhammad Ali was known as the Greatest).
'pen' reversed gives 'nep'.
'nep'+'ali'='NEPALI'
(Other definitions for nepali that I've seen before include "Foreigner" , "Kathmandu native" , "one found in mountainous region" , "Native of one Himalayan state" , "Asian national" .)