conspiracy
Concise Oxford English Dictionary © 2008 Oxford University Press:
conspiracy/kənˈspɪrəsi/
▶noun (pl. conspiracies) a secret plan by a group to do something unlawful or harmful.
■ the action of conspiring.
– phrases
a conspiracy of silence an agreement to say nothing.
a conspiracy of silence an agreement to say nothing.
– origin ME: from Anglo-Norman Fr. conspiracie, alt. of OFr. conspiration, based on L. conspirare (see conspire).
'conspiracy' also found in these Oxford entries:

