A potatis is a swedish word, meaning that you are completely useless. Originally the word translated to potatoe in English, but that meaning has been lost.
Adj. Joking term to describe ones self or others as round, funny looking, or potato shaped. Can also be used as a flirtatious term for someone you like, usually when you are trapped in the friend zone.
Boy: What do you think of yourself? Beautiful, sexy, smart?
Girl: Potatoish
Boy: Potatoish? Thats okay, i like potatos.