Food Terminology Is Nuts
It’s surprisingly difficult to find clear definitions for these terms online:
seed = plant embryo
fruit = seed container
nut = hard-shelled fruit
grain = small, hard seed
cereal = grain-yielding plant
“A legume is a plant in the family Fabaceae” according to Wikipedia. A pulse is legume seed. Beans, lentils, and peas are all pulses. As far as I can tell there’s no real definition for these.