Leader, 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 more senses
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.
Shades of meaning
Fernald lists leader only as an antonym, under accessory.
He lists it without comment; the entries above explain its neighbors.