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

Actually, our country plans to spend up to $1.5 trillion over 30 years to overhaul its nuclear arsenal by rebuilding each leg of the nuclear triad and its accompanying infrastructure. —Bishop Peter A. Rosazza, Hartford Courant, 23 Dec. 2024

And so anytime that triad of injuries showed up, diagnosis of shaken baby syndrome, and then the criminal fallout from that diagnosis. —Taylor Wilson, USA TODAY, 30 Sep. 2024

Using this diagnostic triad, Roberson's trial in Anderson County featured a case from the prosecution that hinged on Roberson as physically abusive. —Ines Chomnalez, Austin American-Statesman, 3 July 2024

Where's the Pardon for Thousands of Black Men Locked Up for What Hunter Did Biden Pardoning Hunter Proves Being a Biden Is a Get Out of Jail Free Card But the Bondi, Patel, Hegseth triad—if it gets assembled—shouldn't be too confident about lawlessly going lawfare nuclear. —Josh Hammer, Newsweek, 3 Dec. 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