Meaning:

the seventh of the Ten Heavenly Stems; age

Origin:

“庚“的本义是“脱谷的农具”。字形是一个架状物，中间有一把上端开叉的打谷器。后多用作天干名。

This character originally meant “threshing tools.” It looks like the frame of a threshing device, the upper part of which was open. Later, it was used as a name of the Heavenly Stems.

Words:

   庚伏   (gēngfú)  : dog day summer

   庚齿   (gēngchǐ): age

   贵庚   (guìgēng): age

Examples:

1. 庚伏是一年中最热的时候。

    Gēngfú shì yìnián zhōng zuìrè de shíhòu

    The dog days are the hottest time of the year.

2. 请问您贵庚？

    Qǐngwèn nín guìgēng

    May I ask how old are you?