Asian runner visiting Germany and America (5)
I believe the answer is:
indus
'asian runner' is the definition.
(I've seen this before)
'visiting germany and america' is the wordplay.
'visiting' becomes 'in'.
'germany' becomes 'd' (vehicle registration code for Deutschland).
'and' says to put letters next to each other.
'america' becomes 'US' (United States).
'in'+'d'+'us'='INDUS'
(Other definitions for indus that I've seen before include "banker" , "River rising in Tibet" , "Great river of South Asia" , "River of Southern Asia" , "River giving its name to an early civilisation" .)