What term describes the angle between the plane of the ecliptic and the plane of the celestial equator?

Answer

Obliquity of the ecliptic

The angle between the ecliptic plane and the celestial equator (the projection of Earth's equator) is defined as the obliquity of the ecliptic.

What term describes the angle between the plane of the ecliptic and the plane of the celestial equator?
sunastronomyorbitCelestial sphereecliptic