Translation guide
The distance from the center to the edge of a circle or sphere, or a specified area around a point.
The straight line from the center to the circumference of a circle or sphere.
The standard mathematical term for radius.
この円の半径は5センチです。
The radius of this circle is 5 cm.
A specified distance from a central point, often used to describe a surrounding area.
Means 'within a radius of ~'. Commonly used with distances.
駅から半径1キロ以内に住んでいます。
I live within a 1 km radius of the station.
Similar to 以内, but 圏内 emphasizes the area as a zone or sphere.
半径500メートル圏内は駐車禁止です。
Parking is prohibited within a 500-meter radius.
Means 'vicinity' or 'surrounding area', often used instead of 'radius' in casual contexts.
The thicker and shorter of the two bones in the human forearm.
Medical term for the radius bone. Not used in everyday conversation.
橈骨を骨折しました。
I fractured my radius.
この周辺に良いレストランはありますか？
Are there any good restaurants in this area?