1N-VAR [oft poss NOUN](人、動物等的)圍長、腰圍 The girth of an object, for example a person's or an animal's body, is its width or thickness, considered as the measurement around its circumference. (人、動物等的)圍長、腰圍 [formal]
A girl he knew had upset him by commenting on his increasing girth.
2N-COUNT (馬的)肚帶,鞍帶 A girth is a leather strap which is fastened firmly around the middle of a horse to keep the saddle or load in the right place. (馬的)肚帶,鞍帶