Ham originally in the German hamper (6)
I believe the answer is:
hinder
'hamper' is the definition.
(I know that hamper can be written as hinder)
'ham originally in the german' is the wordplay.
'originally' indicates taking the first letters.
'the german' becomes 'der' ('the' in German).
The initial letter of 'ham' is 'h'.
'h'+'in'+'der'='HINDER'
(Other definitions for hinder that I've seen before include "Keep back by delaying progress" , "stop" , "Hamper, impede" , "Obstruct or hold back" , "block" .)