(In the context of various conspiracy theories) an unmarked, dark-coloured helicopter believed to be involved in sinister or covert activities, especially relating to the establishment of a global government.
adjective
US
(attributive) of or relating to belief in conspiracies of this type.
Origin
1970s; earliest use found in Havre (Montana) Daily News.
Definition of black helicopter in US English:
black helicopter
noun
US
(In the context of various conspiracy theories) an unmarked, dark-coloured helicopter believed to be involved in sinister or covert activities, especially relating to the establishment of a global government.
adjective
US
(attributive) of or relating to belief in conspiracies of this type.
Origin
1970s; earliest use found in Havre (Montana) Daily News.