- (n.) An opening; a hollow; a bending.
- (n.) A depression between adjoining lobes.
- (n.) A narrow, elongated cavity, in which pus is collected; an elongated abscess with only a small orifice.
- (pl.) of Sinus.
- (n.) A dilated vessel or canal.
- (n.) A cavity; a depression.
- (n.) A bay of the sea; a recess in the shore.
- (n.) A cavity in a bone or other part, either closed or with a narrow opening.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). sinus. Retrieved September 20, 2026, from http://smartdefine.org/sinus/definitions/2062328 |
| Chicago | Webster's. 2011. "sinus" http://smartdefine.org/sinus/definitions/2062328 (accessed September 20, 2026). |
| Harvard | Webster's 2011, sinus, Smart Define, viewed 20 September, 2026, <http://smartdefine.org/sinus/definitions/2062328>. |
| MLA | Webster's. "sinus" 28 May 2011. Web. 20 September 2026. <http://smartdefine.org/sinus/definitions/2062328> |