直径 (zhí jìng): เส้นผ่าศูนย์กลาง

The diameter of this circular flowerbed is five meters, so the workers need to buy a fence long enough to enclose it.

The teacher asked us to measure the diameter of a coin; Xiaoming used a ruler and found it was two centimeters.

The diameter of this old tree is over one meter; it takes three children holding hands to barely wrap their arms around it.

The engineer said the diameter of this water pipe is too small, so the water flow is not fast enough; it must be replaced with a thicker one.