One found next to China (on northeast) (6)
I believe the answer is:
nepali
'one found next to china on northeast' is the definition.
I can't tell whether this definition defines the answer.
'one found next to china on northeast' is the wordplay.
'one' becomes 'i' (Roman numeral).
'found next to' is a charade indicator (letters next to each other).
'china' becomes 'pal' (china plate is Cockney rhyming slang for mate).
'on' says to put letters next to each other.
'northeast' becomes 'NE' (abbreviation).
'i' after 'pal' is 'pali'.
'pali' after 'ne' is 'NEPALI'.
Can you help me to learn more?
(Other definitions for nepali that I've seen before include "Kathmandu native" , "Mountain-dweller" , "One from Katmandu" , "Language of Kathmandu" , "Foreigner" .)