Correct

准点

/ zhǔn diǎn /
Strokes

Example

As an Adjective

on the dot

1
diǎnzhōng
点钟
gōnggòng
公共
chē
汽车
zhǔndiǎn
准点
dàozhàn
到站
  

The bus arrived on the dot of seven o'clock. / The seven o'clock bus arrived on the dot.