secret society

Từ điển WordNet v3.1 - WordNet Dictionary

noun

a society that conceals its activities from nonmembers
• Hypernyms:
association
• Hyponyms:
Freemasonry, Masonry, Rashtriya Swayamsevak Sangh, National Volunteers Association
• Instance Hyponyms:
Ku Klux Klan, Klan, KKK