Jam nut

Nut Nut (n[u^]t), n. [OE. nute, note, AS. hnutu; akin to D. noot, G. nuss, OHG. nuz, Icel. hnot, Sw. n["o]t, Dan. n["o]d.] [1913 Webster] 1. (Bot.) 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. [1913 Webster]

2. A perforated block (usually a small piece of metal), provided with an internal or female screw thread, used on a bolt, or screw, for tightening or holding something, or for transmitting motion. See Illust. of 1st {Bolt}. [1913 Webster]

3. The tumbler of a gunlock. --Knight. [1913 Webster]

4. (Naut.) A projection on each side of the shank of an anchor, to secure the stock in place. [1913 Webster]

5. pl. Testicles. [vulgar slang] [PJC]

{Check nut}, {Jam nut}, {Lock nut}, a nut which is screwed up tightly against another nut on the same bolt or screw, in order to prevent accidental unscrewing of the first nut.

{Nut buoy}. See under {Buoy}.

{Nut coal}, screened coal of a size smaller than stove coal and larger than pea coal; -- called also {chestnut coal}.

{Nut crab} (Zo["o]l.), any leucosoid crab of the genus {Ebalia} as, {Ebalia tuberosa} of Europe.

{Nut grass} (Bot.), See {nut grass} in the vocabulary.

{Nut lock}, a device, as a metal plate bent up at the corners, to prevent a nut from becoming unscrewed, as by jarring.

{Nut pine}. (Bot.) See under {Pine}.

{Nut rush} (Bot.), a genus of cyperaceous plants ({Scleria}) having a hard bony achene. Several species are found in the United States and many more in tropical regions.

{Nut tree}, a tree that bears nuts.

{Nut weevil} (Zo["o]l.), any species of weevils of the genus {Balaninus} and other allied genera, which in the larval state live in nuts. [1913 Webster]