Defn: The shape and size of a book; hence, its external form.

The older manuscripts had been written in a much larger format than that found convenient for university work. G. H. Putnam.

One might, indeed, protest that the format is a little too luxurious.
Nature.

FORMATE
For"mate, n. Etym: [See Formic.] (Chem.)

Defn: A salt of formic acid. [Written also formiate.]

FORMATION
For*ma"tion, n. Etym: [L. formatio: cf. F. formation.]

1. The act of giving form or shape to anything; a forming; a shaping. Beattie.

2. The manner in which a thing is formed; structure; construction; conformation; form; as, the peculiar formation of the heart.

3. A substance formed or deposited.

4. (Geol.) (a) Mineral deposits and rock masses designated with reference to their origin; as, the siliceous formation about geysers; alluvial formations; marine formations. (b) A group of beds of the same age or period; as, the Eocene formation.