What term refers to an imaginary line that passes through Earth's center and its North and South Poles?

The term that refers to an imaginary line passing through Earth's center and connecting the North and South Poles is the axis. The Earth's axis is the line around which the Earth rotates, and it is tilted at an angle of about 23.5 degrees relative to its orbit around the Sun. This axial tilt is responsible for the changing seasons as different parts of the Earth receive varying amounts of sunlight throughout the year.

In contrast, the equator is an imaginary line that circles the Earth horizontally, dividing it into the Northern and Southern Hemispheres, while the diameter refers to the length of a straight line crossing through the center of a circle or sphere. Meridians, on the other hand, are imaginary lines that run from the North Pole to the South Pole, defining longitude, but do not specifically represent the rotational aspect of the Earth like the axis does.