Judd et al say that they're (walnuts) drupes.

Now I am really confused. Does that mean they come in a fleshy outer covering,
like the almond, and what we call the nut is just the seed? I seem to recall
that some of that group, like the hickories, have a sort of outer husk. So
which are the true nuts? And what do you call a cashew?
I guess we never did agree on where to put bananas, except not in the
refrigerator.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)