Meaning of pì:
屁
fart; flatulence; nonsense; (not) a damn thing
Xiǎo gǒu fāle yīgè pì, dàjiā dōu xiàole.
小狗发了一个屁,大家都笑了。
The puppy farted, and everyone laughed.
Tā shuōle yī gè xiàohuà, rě de dàjiā hāhā dàxiào, jiéguǒ yǒurén fàngle gè xiǎngliàng de pì.
他说了一个笑话,惹得大家哈哈大笑,结果有人放了个响亮的屁。
He told a joke that made everyone laugh, and then someone let out a loud fart.
Tā shuō de huà jiǎnzhí shì pìhuà.
他说的话简直是屁话。
What he said is simply nonsense.
Tā shuō de huà wǒ yīgè pì dōu bù xìn.
他说的话我一个屁都不信。
I don't believe a damn thing he says.
(usu. in the negative) what
Nǐ shuō de zhèxiē pì huà yīdiǎn dàolǐ dōu méiyǒu.
你说的这些屁话一点道理都没有。
The nonsense you said makes no sense at all.