triad

[ trahy-ad, -uhd ]

noun

1. a group of three, especially of three closely related persons or things.
2. Chemistry.
   1. an element, atom, or group having a valence of three. Compare monad ( def 2 ), dyad ( def 3 ).
   2. a group of three closely related compounds or elements, as isomers or halides.
3. Music. a chord of three tones, especially one consisting of a given tone with its major or minor third and its perfect, augmented, or diminished fifth.
4. Triad, Military. the three categories of delivery systems for strategic nuclear weapons, namely bombers, land-based missiles, and missile-firing submarines:

   The report says this missile is required in order to sustain an effective air leg of the Triad.

Triad

¹

/ ˈtraɪæd /

noun

1. any of several Chinese secret societies, esp one involved in criminal activities, such as drug trafficking

triad

²

/ ˈtraɪæd /

noun

1. a group of three; trio
2. chem an atom, element, group, or ion that has a valency of three
3. music a three-note chord consisting of a note and the third and fifth above it
4. an aphoristic literary form used in medieval Welsh and Irish literature
5. the US strategic nuclear force, consisting of intercontinental ballistic missiles, submarine-launched ballistic missiles, and bombers

Derived Forms

• triˈadic, adjective
• ˈtriadism, noun

Other Words From

• tri·ad·ic [trahy-, ad, -ik], adjective
• tri·ad·ism noun

Word History and Origins

Origin of triad¹

First recorded in 1540–50; from Latin triad- (stem of trias ), from Greek triás; tri-, -ad ¹

Word History and Origins

Origin of triad¹

C16: from Late Latin trias , from Greek; related to Greek treis three

Example Sentences

It’s worth noting, too, that only one member of the Democratic House leadership triad is not a stalwart moderate, Minority Whip Katherine Clark.

From Slate

Beijing, the senior partner in the triad, seeks to be the stable leader of a new world order, one that is not led by the US.

From BBC

But the land-based part of the triad is actually the opposite of deterrence — it’s an invitation to be attacked.

From Salon

They not only called for cancellation of the Sentinel program for a new version of ICBMs, they also called for getting rid of the entire land-based leg of the triad.

From Salon

And as Norman Solomon and the late Daniel Ellsberg once wrote, “If reducing the dangers of nuclear war is a goal, the top priority should be to remove the triad’s ground-based leg — not modernize it.”

From Salon

Related Words

• triumvirate