Thin a. [Compar. Thiner superl. Thinest.]
 1. Having little thickness or extent from one surface to its opposite; as, a thin plate of metal; thin paper; a thin board; a thin covering.
 2. Rare; not dense or thick; -- applied to fluids or soft mixtures; as, thin blood; thin broth; thin air.
    In the day, when the air is more thin.   --Bacon.
 Satan, bowing low
 His gray dissimulation, disappeared,
 Into thin air diffused.   --Milton.
 3. Not close; not crowded; not filling the space; not having the individuals of which the thing is composed in a close or compact state; hence, not abundant; as, the trees of a forest are thin; the corn or grass is thin.
    Ferrara is very large, but extremely thin of people.   --Addison.
 4. Not full or well grown; wanting in plumpness.
    Seven thin ears . . . blasted with the east wind.   --Gen. xli. 6.
 5. Not stout; slim; slender; lean; gaunt; as, a person becomes thin by disease.
 6. Wanting in body or volume; small; feeble; not full.
    Thin, hollow sounds, and lamentable screams.   --Dryden.
 7. Slight; small; slender; flimsy; wanting substance or depth or force; superficial; inadequate; not sufficient for a covering; as, a thin disguise.
    My tale is done, for my wit is but thin.   --Chaucer.
 Note: ☞ Thin is used in the formation of compounds which are mostly self-explaining; as, thin-faced, thin-lipped, thin-peopled, thin-shelled, and the like.
 Thin section. See under Section.