Meaning of tetrad | Babel Free

Definitions

1. A group of four things.
2. Two pairs of sister chromatids (a dyad pair) aligned in a certain way and often on the equatorial plane during the meiosis process.
3. A group of four haploid and immature pollen grains in tetrahedral fashion produced by meiotic microsporogenesis.
4. A unit of land area of two by two (that is, four) square kilometres.
5. A tetravalent atom or radical.
6. A group of four basis vectors for a four-dimensional manifold in differential geometry.
7. A chord comprised of four notes; a tetrachord.

Equivalents

Examples

“Religious movements and cults are often founded on a tetrad of elements: a prophet, a prophecy, a book, and a revelation.”

“They took figures for the abundance of invasive weeds mapped according to the normal grid unit of the 'hectad', or 10 × 10 km square, and then looked at how abundant these species were mapped at a much finer scale – in 'tetrads', or 2 × 2 km squares, inside these hectads.”

CEFR level