Reference for Chullin 49:4

אמר קרא

You must say: It is an earthenware vessel.<span class="x" onmousemove="('comment',' The fact that the verse specifically mentions 'open' suggests immediately that it is dealing with an earthen vessel which has a special rule concerning its 'opening' i.e., its air-space, for no other vessel can be rendered unclean or can convey uncleanness through its air-space.');">³</span>

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow

Jastrow