Beast runs right round one German river (8)
I believe the answer is:
reindeer
'beast' is the definition.
(I've seen this before)
'runs right round one german river' is the wordplay.
'runs' becomes 'r' (cricket abbreviation).
'right' becomes 'r' (common abbreviation).
'round' indicates putting letters inside.
'one german' becomes 'ein' ('one' in German).
'river' becomes 'dee' (River Dee).
'r'+'r'='rr'
'ein'+'dee'='eindee'
'rr' enclosing 'eindee' is 'REINDEER'.
(Other definitions for reindeer that I've seen before include "Dancer, Prancer etc." , "Rudolph, for example" , "Eg, caribou" , "Large animal of northern regions" , "Christmas card creatures" .)