It is called a fissure
Craks, crater
cleavage
Slate has been quarried and split to make roofing slates for centuries. It splits easily (after a bit of practise) and is very durable.
Slate is the metamorphic rock formed from shale. A pile of mud can turn into shale (a fine-grained sedimentary rock) with relatively low pressure, about 3 mi (5 km) down into the earth. With more pressure and some heat, shale can transform into slate. Metamorphic rock found closer to Earth's surface, or produced by low pressure, characteristically splits or flakes into layers of varying thickness. This is called foliation. Slate is often used as roofing tiles and paving stones.
foliated
The plural of split is splits. As in "the acrobat can do splits easily".
Pumice.
a bisector splits an angle into to congruent angles(also called an angle bisector)
When ballet dancers do the splits in the air it is usually called a spilt leap or a center leap.
because your legs look like 1 banana in a banana split.
FISSION
Horcrux
The abdominal aorta splits at about the lumbosacral joint into two common iliac arteries.
It is called a fissure
It is a sedimentary rock that easily splits into layers. It is also the parent rock of Slate.
When an atom splits, its called fission Heat comes from fission