decimal point       
noun [ C ] uk/ˌdes.ɪ.məl ˈpɔɪnt/ us/ˌdes.ɪ.məl ˈpɔɪnt/
 小数点
the dot used between the whole numbers and the tenths of a decimal. In some countries a decimal comma is used instead.
  To divide by ten, move the decimal point one place to the left. 要除以10,将小数点左移一位。 
 See also: point noun