triad

noun

tri·​ad ˈtrī-ˌad 

 also  -əd

1

: a union or group of three : trinity

2

: a chord of three tones consisting of a root with its third and fifth and constituting the harmonic basis of tonal music

triadic

trī-ˈa-dik 

adjective

triadically

trī-ˈa-di-k(ə-)lē 

adverb

Did you know?

The best-known type of triad is a type of musical chord consisting of three notes. A D-major triad is made up of the notes D, F-sharp, and A; an F-minor triad is made up of F, A-flat, and C; and so on. Major and minor triads form the basis of tonal music, and songs and other pieces usually end with a triadic harmony. In medicine, a triad is a set of three symptoms that go together. The Chinese criminal organizations called triads got their name from the triangular symbol that they used back when they began, centuries ago, as patriotic organizations. Today, with over 100,000 members, the triads operate in the U.S., Canada, and many other countries.

Synonyms

• threesome
• trifecta
• trinity
• trio
• triple
• triplet
• triumvirate

Examples of triad in a Sentence

a triad of candlesticks on the mantel

Recent Examples on the Web

The triad are competing against Councilmember Hung Wei, former mayors Gilbert Wong and Barry Chang and political newcomer Claudio Bono. —Stephanie Lam, The Mercury News, 7 Nov. 2024

On Potomac specifically, all the women are trapped by the triad of patriarchy, respectability, and desirability. —Shamira Ibrahim, Vulture, 4 Nov. 2024

Here are the three essential ingredients–the triad of transformative learning–that make learning programs truly impactful. —William Arruda, Forbes, 3 Nov. 2024

Why did clinicians wrongly trust this triad of symptoms for so long? —Jeff Kukucka, Scientific American, 26 Oct. 2024

Word History

Etymology

Latin triad-, trias, from Greek, from treis three

First Known Use

1546, in the meaning defined at sense 1

Kids Definition

triad

noun

tri·​ad ˈtrī-ˌad 

 also  -əd

1

: a union or group of three usually closely related persons or things

2

: a chord made up usually of the first, third, and fifth notes of a scale

triadic

trī-ˈad-ik 

adjective

Medical Definition

triad

noun

tri·​ad

ˈtrī-ˌad also -əd

1

: a union or group of three

a triad of symptoms

2

: a trivalent element, atom, or radical

triadic

trī-ˈad-ik 

adjective