Definitions:
- a skullcap worn by Roman Catholic priests
- The vertical central area of the crown of a bird's head.
- A round cavity or depression, in the form of a cup or cap, lathed and plastered; used to diminish the rise or elevation of a moderate chapel, alcove, etc. which would otherwise be too high for other pieces of the apartment.
- The upper (superior) or lower (inferior) half of the globe of the eye.