短径

1. Origins, structure, and basic meaning

• Structure: 短径 is read as たんけい; 短 (short) and 径 (diameter) denote the full minor-axis length through the center of an ellipse.
• Basic usage: Use 楕円の短径を測る for measurement and 長径と短径の長さ for the paired major and minor dimensions.

2. Common pitfalls and similar expressions

• Pair with 長径
  • 長径 is the longest central diameter of the ellipse, while 短径 is the shorter central diameter perpendicular to it.
• Not a radius
  • 短径 is the full distance across the ellipse, not the half-length from its center to one edge.