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Number & MeasureGreekEnglish

Triad

/ˈtraɪæd/noun

A set of three things treated together, and in music a chord of three notes.

The Greek roots

τριάς
triás
group of three

Literally: a group of three

Follow a root:τριάς1 word

The story of the word

Theophilus of Antioch used τριάς of the Christian Trinity in the second century, the earliest surviving Greek in that sense, and Latin answered with trinitas. Musicians took the same word for three notes stacked in thirds, the chord that decides whether a piece sounds major or minor. The Hong Kong secret societies were called Triads by the British after their emblem, a triangle standing for heaven, earth and man.

How it travelled
Ancient Greek → Late Latin → English
First recorded
16th century

Same family

trilogytripodtriptychtriode

In a sentence

Drop the third out of the triad and the chord stops taking sides.

The report keeps returning to the same triad of causes.

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