pentad

American  

[pen-tad] / ˈpɛn tæd /

noun

1. a period of five years.

2. a group of five.

3. the number five.

4. Chemistry. a pentavalent element or group.

5. Climatology. a period of five consecutive days.

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pentad British  

/ ˈpɛntæd /

noun

1. a group or series of five

2. the number or sum of five

3. a period of five years

4. chem a pentavalent element, atom, or radical

5. meteorol a period of five days

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Etymology

Origin of pentad

First recorded in 1645–55; from Greek pentad- (stem of pentás ) group of five; see origin at pent-, -ad ¹

Example Sentences

In the pentad of 1923-27, U. S. investors paid $34,806,783,000 for 36,965 different issues of bonds and stocks.

From Time Magazine Archive

An element having a valence of one is a monad; of two, a dyad; three, a triad; four, tetrad; five, pentad; six, hexad, etc.

From An Introduction to Chemical Science by Williams, Rufus Phillips

All things in which the temporal is concerned may be reduced to a pentad, namely, prothesis, thesis, antithesis, mesothesis and synthesis.

From The Literary Remains of Samuel Taylor Coleridge by Coleridge, Henry Nelson

In chapters xvii.-xix. most of the original laws are still arranged in the decalogue and pentad form.

From The Origin and Permanent Value of the Old Testament by Kent, Charles Foster

Colours may best be expressed by a heptad, the largest possible formula for things finite, as the pentad is the smallest possible form.

From Specimens of the Table Talk of Samuel Taylor Coleridge by Coleridge, Henry Nelson