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thin (thĭn)
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adj. thin·ner, thin·nest
1.
a. Relatively small in extent from one surface to the opposite, usually in the smallest solid dimension: a thin book.
b. Not great in diameter or cross section; fine: thin wire.
2. Having little bodily flesh or fat; lean or slender.
3.
a. Not dense or concentrated; sparse: the thin vegetation of the plateau.
b. More rarefied than normal: thin air.
4.
a. Flowing with relative ease; not viscous: a thin oil.
b. Watery: thin soup.
5.
a. Sparsely supplied or provided; scanty: a thin menu.
b. Having a low number of transactions: thin trading in the stock market.
6. Lacking force or substance; flimsy: a thin attempt.
7. Lacking resonance or fullness; tinny: The piano had a thin sound.
8. Lacking radiance or intensity: thin light.
9. Not having enough photographic density or contrast to make satisfactory prints. Used of a negative.
adv.
1. In a thin manner: Spread the varnish thin if you don't want it to wrinkle.
2. So as to be thin: Cut the cheese thin.
tr. & intr.v. thinned, thin·ning, thins
To make or become thin or thinner.
[Middle English, from Old English thynne; see ten- in the Appendix of Indo-European roots.]
thinly adv.
thinness n.
thinnish adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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