the distance around the outside of a thick or fat object, like a tree or a body

The oak was two metres in girth. 这棵橡树干围长两米。

humorous His ample girth was evidence of his love of good food. 他那粗大的腰身表明他极其贪吃。

the strap that goes around the middle of a horse to keep the saddle (= rider's seat) or the load in the right position

Loosen the girth a little. 把马的肚带松一松。