Language / Polish insult that sounds kinda like " e sha vees ta" ? [16]

so, i double checked with my mom and she said phonetically it was like e sha veestray. i think that is more like it. yes, it was vulgar- go take a shit? definately. but an insult nonetheless, no? i am saying/spelling it best i can the way it sounded in english (does that make sense?)

also, as far as ja ja being slang for testicles, maybe i have spelling wrong but that is what we called him. he and grandma both came as first generation polish to america, spoke fluent polish as well as read and wrote it. they refused to teach their kids because that way they could communicate without being "heard". im sure my grandfather would never allow us grandkids to say a bad word! he took it as a term of endearment, so obviously there is something lost in translation!