Radius
noun
Half a diameter is a radius.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
この円の半径は10センチです。
The radius of this circle is ten centimeters.
半径5km以内にコンビニが5つもあります。
There are five convenience stores within a five kilometer radius.
僕、半径50cm以内に猫がいないとメンタルがボロボロになる体質なんです。
I'm the type of person whose mental health falls apart if there's no cat within a fifty centimeter radius.
半径3cmの球体の体積は何立方センチメートルですか。
What is the volume in cubic centimeters of a sphere with a radius of three centimeters?