A nut is a fruit composed of a hard shell and a seed, which is generally edible. In botany, there is an additional requirement that the shell does not open to release the seed (indehiscent). In a general context, a wide variety of dried seeds are called nuts, and the translation of "nut" in certain languages frequently requires paraphrases, as the word is ambiguous.
Most seeds come from fruits that naturally free themselves from the shell, unlike nuts such as hazelnuts, chestnuts, and acorns, which have hard shell walls and originate from a compound ovary. The general and original usage of the term is less restrictive, and many nuts, such as almonds, pecans, pistachios, walnuts, and Brazil nuts, are not nuts in a botanical sense. Common usage of the term often refers to any hard-walled, edible kernel as a nut.
All true histories contain instruction; though, in some, the treasure may be hard to find, and when found, so trivial in quantity, that the dry, shrivelled kernel scarcely compensates for the trouble of cracking the nut.
Anne Brontë, in Agnes Grey (1847), Ch. I: The Parsonage.
The thievish jay Seeking her food, with ease might have purloined The auburn nut that held thee, swallowing down Thy yet close-folded latitude of boughs And all thine embryo vastness at a gulp. But fate thy growth decreed
He shewed me a little thing, the quantity of an hazel-nut, in the palm of my hand; and it was as round as a ball. I looked thereupon with eye of my understanding, and thought: What may this be? And it was answered generally thus: It is all that is made. I marvelled how it might last, for methought it might suddenly have fallen to naught for little.
The body was born and it will die. But for the soul there is no death. It is like the betel-nut. When the nut is ripe it does not stick to the shell. But when it is green it is difficult to separate it from the shell. After realizing God, one does not identify oneself any more with the body. Then one knows that body and soul are two different things.
Ramakrishna, The Gospel of Sri Ramakrishna (1942), p. 319.
Sweet is the rose, but grows upon a brere; Sweet is the juniper, but sharp his bough; Sweet is the eglantine, but sticketh nere; Sweet is the firbloome, but its braunches rough; Sweet is the cypress, but its rynd is tough; Sweet is the nut, but bitter is his pill; Sweet is the broome-flowre, but yet sowre enough; And sweet is moly, but his root is ill.
The bodie bigge, and mightely pight, Thoroughly rooted, and of wond'rous hight; Whilome had bene the king of the field, And mochell mast to the husband did yielde, And with his nuts larded many swine.
Kawi pawh a kawm a ṭhat chuan a rah pawh a ṭha, a kawm a chhiat chuan a rah pawh a chhia.
Literal: If the shell of Kawi is good, the nut it bears is also good; if the shell is not good, the nut inside is also poor. (Kawi is a large been-like seed or nut.)
Mizo proverb, reported in C. Saizawna, Pipute ṭawngkauchheh and M.D. Muthukumaraswamy, Folklore as a Discourse, Univ. of Madras, Dept. of Anthropology, National Folklore Support Center (India).