Copyright a German article about very strong stimulant (8)
I believe the answer is:
caffeine
'stimulant' is the definition.
(I've seen this before)
'copyright a german article about very strong' is the wordplay.
'copyright' becomes 'C' (as in the copyright symbol, a C in a circle).
'german article' becomes 'eine' (indefinite article in German).
'about' says to put letters next to each other.
'very strong' becomes 'ff' (musical abbreviation for fortissimo, 'very strong').
'eine' put after 'ff' is 'ffeine'.
'c'+'a'+'ffeine'='CAFFEINE'
(Other definitions for caffeine that I've seen before include "coffee ingredient" , "Compound in coffee" , "Stimulant found in many beverages" , "Stimulating alkaloid" , "Stimulant in, eg, cappuccino" .)