The fruit of certain trees and shrubs (as of the almond, walnut, hickory, beech, filbert, etc.), consisting of a hard and indehiscent shell inclosing a kernel.
- An indehiscent, hard-shelled, one-loculated, one-seeded fruit, such as an acorn or hazelnut.
- A seed borne within a fruit having a hard shell, as in the peanut, almond, or walnut.
- The kernel of any of these.
- Slang A crazy or eccentric person.
- Slang 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 ridge of wood at the top of the fingerboard or neck of a stringed instrument, over which the strings pass.
- Music 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 The cost of launching a business venture.
- Slang 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).
- Vulgar Slang A testicle.
- To gather or hunt for nuts.