| # | Concept | Culture | Statement | Freq. |
|---|---|---|---|---|
| 1 | annulus | mathematics | In mathematics and physics, an annulus is a ring-shaped object defined by two concentric circles. | 1 |
| 2 | annulus | mathematics | In mathematics and science, an annulus is a region between two concentric circles. | 1 |
| 3 | annulus | mathematics | In mathematics and engineering, an annulus refers to a ring-shaped geometric figure with an inner and outer radius, commonly used in calculations and designs. | 1 |