Definition of Geoid

What is a Geoid?

A Geoid is a special model of the Earth’s shape. It tells us how the Earth would look if there was no land or water on it, only the gravitational pull. It is like a bumpy sea, with some parts higher and some lower.

Origin of Geoid

The Geoid’s shape comes from the Earth’s gravity, which is not the same everywhere. Gravity is stronger in some places due to more mass underneath, like mountains or big buildings. Scientists use data from satellites to measure the strength of gravity and then create a model of the Earth using the geoid shape.

Everyday Life

You might not see or hear about the Geoid directly in everyday life, but it is very helpful for things like GPS navigation systems. GPS devices use the Geoid’s shape to calculate your exact location on Earth.

Synonyms and Comparison

The Geoid is often called the “Earth’s true shape” because it takes into account the gravitational pull. It is different from a globe or model of the Earth that you might be familiar with, which usually shows a smooth ball without bumps.


The Geoid is a special model that shows the true shape of the Earth, taking into account gravity. It helps us understand how gravity pulls on different parts of our planet. Next time you use a GPS, remember it’s thanks to the Geoid that it can tell you exactly where you are!