Key Difference: The axis is an imaginary line through both the north and south poles around which the Earth rotates. The equator is the point from which the latitude is calculated. In other words, it is the 0° latitude line.

An axis may be defined as an imaginary line around which the object spins. The Earth’s rotation is the best example to understand an axis. Earth rotates from west to east around an imaginary line, which passes through the poles, i.e. north and south poles. It is perpendicular to the plane of the equator. Thus, this imaginary line is called the axis of Earth’s rotation. This is the only reason that the celestial bodies appear to move from east to west. The earth spins on an axis, unlike a top or rolling ball, it does not spin perfectly horizontally or vertically. Instead, it spins at a 23.5 degree tilt. This tilt is also what is responsible for different climates and seasons at different times on the planet.

Axis is commonly referred to in mathematics. An axis of symmetry is a line, which divides a two-dimensional object into identical shapes. An axis may also be referred to in science, in technology, in music, in industry, in geography, etc.

The equator is the point from where the latitude is calculated. In other words, it is the 0° latitude line. The term equator is derived from the Latin, 'circulus aequator diei et noctis', meaning ‘circle equalizing day and night’. It is one of the main imaginary circles on latitude, which actually is based on the relationship between the Earth’s axis of rotation. In simple terms, equator is the imaginary circle, which cuts the spherical Earth exactly in the middle, i.e. in two halves. The Earth's axis along the equator at one revolution per sidereal day is 0.0339 m/s².

Comparison between Axis and Equator:

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