Is it correct to think that these to verbs have a spatial orientation: 'pivot' and 'spin'?

... so 'pivot': is more like a rotation around the horizontal axis, whereas 'spin' - is more like around the vertical one? In what cases 'pivot' is actually used to indicate rotation, turning around?

Hello everyone! And thank you!

Solution 1:

According to Wikipedia, a pivot is the center point of any rotational system. The key word is point.

Also according to Wikipedia:

A rotation is a circular movement of an object around a center (or point) of rotation. A three-dimensional object can always be rotated about an infinite number of imaginary lines called rotation axis [sic]. If the axis passes through the body's center of mass, the body is said to rotate upon itself, or spin. [Emphasis mine.]

It's incorrect to think of pivot as meaning "more like a rotation around the horizontal axis" -- a pivot is a point, not an axis. It's also incorrect to think of spin as meaning "more like [rotation] around the vertical one" -- the axis could have any spatial orientation.

Addendum: As @PeterShor correctly notes in the comment below, a pivot can also be a shaft or a pin on which something turns. Taking that as the definition, one can still assert that a pivot is not "more like a rotation about a horizontal axis": the shaft or pin could be oriented in any direction in space.

For completeness, Lexico defines pivot as follows:

pivot: The central point, pin, or shaft on which a mechanism turns or oscillates.

Addendum 2: In the above, I was focused on pivot as a noun, as pointed out to me by @HotLicks. As per Lexico, pivot as a verb means "turn on or as if on a pivot." If you take the Lexico definition of pivot as a noun, pivot as a verb means to turn or oscillate "on a central point, pin, or shaft". Again, there is no implication that the turning or oscillating is about a horizontal axis.

Bottom line: Neither pivot nor spin carry any implication of spatial orientation, vertical, horizontal, or otherwise.

Solution 2:

• spin verb (TURN): to (cause to) turn around and around, especially fast:

  • The earth spins on its axis.
  • The roulette players silently watched the wheel spin around/round.

• pivot verb (TURN) to turn or twist:

  • She pivots her left foot.
  • He pivoted on his heels and headed out.
  • Future deals will pivot on (= depend on) easing commercial conflicts.

I think this answers my question.