The Asian child I had seen running by (7)
I believe the answer is:
chinese
'the asian' is the definition.
(Chinese is an example)
'child i had seen running by' is the wordplay.
'child' becomes 'ch' (abbreviation for child).
'had' says to put letters next to each other.
'running' indicates an anagram (the letters run around to different places).
'by' is a charade indicator (letters next to each other).
'seen' anagrammed gives 'nese'.
'ch'+'i'+'nese'='CHINESE'
(Other definitions for chinese that I've seen before include "Language spoken by many" , "Widely-spoken language" , "Boxes within boxes" , "from the east" , "Foreign" .)