Leader \Lead"er\, n.

1. One who, or that which, leads or conducts; a guide; a conductor. Especially:
   (a) One who goes first.
   (b) One having authority to direct; a chief; a commander.
   (c) (Mus.) A performer who leads a band or choir in music; also, in an orchestra, the principal violinist; the one who plays at the head of the first violins.
   (d) (Naut.) A block of hard wood pierced with suitable holes for leading ropes in their proper places.
   (e) (Mach.) The principal wheel in any kind of machinery. [Obs. or R.]

--G. Francis.
   (f) A horse placed in advance of others; one of the forward pair of horses.

He forgot to pull in his leaders, and they gallop away with him at times. --Hare.
   (g) A pipe for conducting rain water from a roof to a cistern or to the ground; a conductor.
   (h) (Fishing) A net for leading fish into a pound, weir, etc.; also, a line of gut, to which the snell of a fly hook is attached.
   (i) (Mining) A branch or small vein, not important in itself, but indicating the proximity of a better one.

2. The first, or the principal, editorial article in a newspaper; a leading or main editorial article.

3. (Print.)
   (a) A type having a dot or short row of dots upon its face.
   (b) pl. a row of dots, periods, or hyphens, used in tables of contents, etc., to lead the eye across a space to the right word or number.

Syn: chief; chieftain; commander. See Chief.

Source: Webster's Revised Unabridged Dictionary (1913)