Definition of Sinus

Sinus

1. of Sinus
2. An opening; a hollow; a bending.
3. A bay of the sea; a recess in the shore.
4. A cavity; a depression.
5. A cavity in a bone or other part, either closed or with a narrow opening.
6. A dilated vessel or canal.
7. A narrow, elongated cavity, in which pus is collected; an elongated abscess with only a small orifice.
8. A depression between adjoining lobes.