Best definition
A cute little itsy bitsy hat worn on the back the head at a jewishnessly jewish party.
OMG!!! your wearing a yamika that is soooo totally crackerjack! breaks out in song

person #1: Jewish jewish jewish

person #2: The rabbi is here, the rabbi is here, the rabbi is here

person #3: yamika yamika yamika

(all at the same time) …something everyone in my history book is wearing!!!