primary wave

American  

noun

1. Seismology. P wave.

---

primary wave Scientific  

1. A type of seismic body wave in which rock particles vibrate parallel to the direction of wave travel. Primary waves are alternatingly compressional and extensional, and cause the rocks they pass through to change in volume. These waves are the fastest traveling seismic waves and can travel through solids, liquids, and gases.

2. Also called P wave

3. See Note at earthquake

---

Etymology

Origin of primary wave

First recorded in 1915–20

Example Sentences

The first wave is a sound wave–like primary wave, or P-wave, moving at about four miles per second.

From Slate • Apr. 18, 2018

The conception of the lamina leads immediately to two schemes, according to which a primary wave may be supposed to be broken up.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 4 "Diameter" to "Dinarchus" by Various

In this case the motion in different directions varies as cosθ, vanishing at right angles to the direction of propagation of the primary wave.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 4 "Diameter" to "Dinarchus" by Various

But a little consideration will prove that in that case the series of secondary waves could not reconstitute the primary wave.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 4 "Diameter" to "Dinarchus" by Various

It is accordingly necessary to suppose that the secondary waves start with a phase one-quarter of a period in advance of that of the primary wave at the surface of resolution.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 4 "Diameter" to "Dinarchus" by Various