geo?
geology...?
in term of shape
Papatuanuku is the earth mother (akin to other other religion/peoples Gaea) so Papa is used for the word earth or ground. If you are meaning Earth as in planet earth then the term used is Te Ao.
The term "Earth sibling" is not a commonly recognized term. It may refer to the relationship between Earth and other celestial bodies in the solar system, such as Mars, Venus, or the Moon, which are also considered part of the Earth's cosmic family.
Antipode is a geographical term used to define points that are diametrically opposed to or exactly the opposite of each other. When two points are antipodal to each other, they are connected by straight line that runs through Earth's center.
" year "
The term Earthling came from the people who inhabit planet Earth. There are also some other terms used such as Gaian, due to the name Gaia used for Earth, and Terran, based of the name Terra, which also means Earth.
normal force
It is the heliocentric model.
The African Luhya term for the English 'earth' is Eshialo.
So far no other life have been discovered beyond Earth but the generic term for such lifeforms would be 'aliens'.
Earth's core