The walnut is an oval nut with a pale tan, slightly warty shell of two halves. Inside there are two halves of the nut looking almost like a small pair of lungs, or a halved brain. In many languages the word for walnut is the default word for nut, so it’s worth checking what you are getting.
When my father invited my mother to meet his parents they had dinner. My mother was nervous and her prospective in-laws were rather distant and formal. My father, before my mother came carefully split several walnuts, removed the nuts and glued the shells back together. He then placed all the doctored walnuts on her side of the nut dish. At the end of the dinner she was offered the nuts. The first one she cracked was empty, as was the second, the third and so on. Bad daddy. Walnuts grew around the house where I was born and raised. Every year we harvested them and laid them out in the greenhouses to dry, and, boy, did our hands get black when we peeled off the green outer casings. What fun.