rod

1. A straight and slender stick; a wand; hence, any slender bar, as of wood or metal (applied to various purposes). Specifically: An instrument of punishment or correction; figuratively, chastisement. "He that spareth his rod hateth his son." (Prov. Xiii. 24)

A kind of sceptor, or badge of office; hence, figuratively, power; authority; tyranny; oppression. "The rod, and bird of peace." .

A support for a fishing line; a fish pole.

<machinery> A member used in tension, as for sustaining a suspended weight, or in tension and compression, as for transmitting reciprocating motion, etc.; a connecting bar.

An instrument for measuring.

2. A measure of length containing sixteen and a half feet; called also perch, and pole. Black rod.

<anatomy> Rods and cones, the elongated cells or elements of the sensory layer of the retina, some of which are cylindrical, others somewhat conical.

Origin: The same word as rood. See Rood.

Source: Websters Dictionary