the dry, one-seeded fruit of any of various trees or shrubs, consisting of a kernel, often edible, in a hard and woody or tough and leathery shell, more or less separable from the seed itself, as the walnut, pecan, chestnut, acorn, etc.
the kernel, or meat, of such a fruit
loosely any hard-shell fruit that will keep more or less indefinitely, as a peanut, almond, etc.
a small block, usually of metal, with a threaded hole through the center, for screwing onto a bolt, screw, etc.
a ridge of ebony or other hard material at the top of the fingerboard of a stringed instrument, over which the strings pass
the small knob at the end of a violin bow, for tightening or loosening the hairs
Informal the initial cost of an undertaking, or the amount of money it is necessary to take in before a profit is realized on it
a. An indehiscent, hard-shelled, one-loculated, one-seeded fruit, such as an acorn or hazelnut.
b. A seed borne within a fruit having a hard shell, as in the peanut, almond, or walnut.
c. The kernel of any of these.
Slang
a. A crazy or eccentric person.
b. An enthusiast; a buff: a movie nut.
Informal A difficult endeavor or problem: Painting the closet was a tough nut to crack.
Slang The human head.
Music
a. A ridge of wood at the top of the fingerboard or neck of a stringed instrument, over which the strings pass.
b. A device at the lower end of the bow for a stringed instrument, used for tightening the hairs.
A small block of metal or wood with a central, threaded hole that is designed to fit around and secure a bolt or screw.
Slang
a. The cost of launching a business venture.
b. The operating expenses of a theater, theatrical production, or similar enterprise: “The [theater] has simply failed to attract enough paying customers per week to meet its nut”(Variety).