Definition of: thin

(thin) adjective thin·ner, thin·nest
1. Having opposite surfaces relatively close to each other; being of little depth or width; not thick.
2. Lacking roundness or plumpness of figure; lean; slender.
3. Having the component parts or particles scattered or diffused; not dense or abundant; sparse; rare: thin ranks, thin gas.
4. Having little body or substance; of a loose texture; hence, insufficient to conceal or cover: thin clothing; flimsy: a thin excuse.
5. Having little or no consistency, as a liquid: thin molasses.
6. Lacking in essential ingredients or qualities: thin blood.
7. Having little volume or richness; shrill or metallic, as a voice.
8. Not abundantly supplied or furnished; bare; scant: a thin table.
9. Not having sufficient contrasts of shade to print well: said of a photographic negative.
10. Lacking vigor or force; feeble; superficial: thin wit. See synonyms under FINE¹, GAUNT, MEAGER.
—v.t. & v.i. thinned, thin·ning To make or become thin or thinner. [OE thynne]
—thin′ly adverb
—thin′ness noun