[sem-ee-mahy-ner, sem-ahy-, sem-ee-, sem-ahy-] 
| 1. | Geometry. one half the minor axis of an ellipse. |
| 2. | Astronomy. one half the minor axis of the ellipse that one celestial body describes around another, as a planet around the sun. |
| semiminor axis | |
noun | |
| one-half the minor axis of an ellipse |
iˈmaɪ