A childhood belief about general

My grandfather told me the round green fruit in canned fruit cocktail were "geezleberries." For years, I only had a mild curiosity as to why I never saw any raw (i.e. not canned) geezleberries, and my family always jokingly referred to canned grapes as "geezleberries", ha ha ha. Only I wasn't in on the joke. I was well into my twenties when my younger sister perceived that I really thought they were called geezleberries and convinced me (with some difficulty) that they were grapes.