What is circumcised mean cos my mum said to my dad I had to have it done?

Hi I'm ben and I'm 12 years old!!!!!!!!!!!!!! My mum has been acting so weird latly she keeps talking to my dad quietly saying stuff like about "circumsatioon" or sumthing. I dont know wat that is but it sounds bad....!! And this afternoon my mum says I'm going to the doctors. And I'm missing school yes!! But it's so weird this morning my mum told me to wash underneath my foreskin on my willy in the shower. Why is she being so weird?