Meaning of TRIAD in English

TRIAD

tri ‧ ad /ˈtraɪæd/ BrE AmE noun [countable]

[ Date: 1500-1600 ; Language: French ; Origin: triade , from Latin , from Greek , from treis 'three' ]

1 . a Chinese secret criminal group

2 . a group of three people or things that are related or similar to each other

Longman Dictionary of Contemporary English.      Longman - Словарь современного английского языка.