mas ‧ ter ‧ stroke /ˈmɑːstəstrəʊk $ ˈmæstərstroʊk/ BrE AmE noun [countable]
a very clever, skilful, and often unexpected action that is completely successful:
That ad campaign was an absolute masterstroke.
masterstroke of
a masterstroke of diplomacy
MASTERSTROKE
Meaning of MASTERSTROKE in English
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012