The helix, or hilus
Concave
One of the differences between a bay and a gulf is that a bay has an inward land curve. The Hudson Bay has an inward curve.
zig
Yes.
A lenses that curve outward is convex.A lenses that curve inward is concave.
A converging lens, also known as a convex lens, bends light inward towards a focal point. This type of lens is thicker in the middle than at the edges and is commonly used in magnifying glasses and camera lenses.
It is called a concave mirror. Concave mirrors curve inward and have reflective surfaces that cave inwards. They can be used to focus light to create real or virtual images.
Could mean you have Rickets
Both sides of a lens curve inward.
The curve moves inward
The curve moves inward