Greetings and respect!

My wife is searching for the proper spelling of a nickname her grandmother used to call her as a child..the grandmother recently passed away, and my wife is looking to use the word in a way that will memorialize their relationship, and honor her Czech heritage. Perhaps a tattoo, or a decorative plaque with a picture of them, when my wife was a child.

Anyway, on to the word in question:

grandma always called my wife "pish - ee - yoink - a"., and grandma always said it meant "little pisser".

Google helped me find you guys, so I ask - is there such a word? was grandma making stuff up? if it's a slang word, how was it spelled?

Thank you for any assistance.