definition of ] botanical
botanical adjective [not gradable]. › ​relating to ​plants or the ​scientific ​study of ​plants: a botanical ​garden botanical ​specimens. (Definition of botanical from the Cambridge Academic Content Dictionary © Cambridge University Press). See all translations.
A nut is a fruit composed of a hard shell and a seed, where the hard-shelled fruit does not open to release the seed. So, while, in a culinary context, a wide variety of dried seeds are often called nuts, in a botanical context, only ones that include the indehiscent fruit are considered true nuts.