stratum

[ strey-tuh m, strat-uh m ]

/ ˈstreɪ təm, ˈstræt əm /

SEE MORE SYNONYMS FOR stratum ON THESAURUS.COM

noun, plural stra·ta [strey-tuh, strat-uh] /ˈstreɪ tə, ˈstræt ə/, stra·tums.

a layer of material, naturally or artificially formed, often one of a number of parallel layers one upon another: a stratum of ancient foundations.

one of a number of portions or divisions likened to layers or levels: an allegory with many strata of meaning.

Geology. a single bed of sedimentary rock, generally consisting of one kind of matter representing continuous deposition.

Biology. a layer of tissue; lamella.

Ecology. (in a plant community) a layer of vegetation, usually of the same or similar height.

a layer of the ocean or the atmosphere distinguished by natural or arbitrary limits.

Sociology. a level or grade of a people or population with reference to social position, education, etc.: the lowest stratum of society.

Linguistics. (in stratificational grammar) a major subdivision of linguistic structure.Compare level(def 17).

Nearby words

stratopause, stratosphere, stratospheric, stratovolcano, stratton, stratum, stratum compactum, stratum corneum, stratum functionale, stratum lucidum, stratum spongiosum

Origin of stratum

1590–1600; < Latin strātum literally, a cover, noun use of neuter of strātus, past participle of sternere to spread, strew, equivalent to strā- variant stem + -tus past participle suffix

Related forms

stra·tous, adjective

Usage note

Strata, historically the plural of stratum, is occasionally used as a singular: The lowest economic strata consists of the permanently unemployable. Less frequently, a plural stratas occurs: Several stratas of settlement can be seen in the excavation. At present, these uses are not well established, and they are condemned in usage guides. Strata may eventually become part of a group of borrowed plurals that are now used as singulars in English, such as agenda and candelabra, but it is not yet in that category. See also agenda, criterion, media, phenomenon.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for stratum

But their young deputies and ministerial director generals tended to be from this recently-returned, Western-educated stratum.
A Ray of Light in Islamist Gloom|Benny Morris|July 17, 2012|DAILY BEAST
The stratum containing the Cudahy local fauna immediately underlies the Pearlette Ash.
Evolution and Classification of the Pocket Gophers of the Subfamily Geomyinae|Robert J. Russell
The stratum from which the jaw was taken was intact and had never been disturbed.
A Manual of the Antiquity of Man|J. P. MacLean
But a second was found in the stratum above (see the Illustration, No. 35, at the end of the Introduction).
Troy and its Remains|Henry (Heinrich) Schliemann

Next above this stratum was one in which types of painted pottery similar to that of the Philistines came to light.
Archology and the Bible|George A. Barton
In the first stratum we have the remains of "the original kernel."
Homer and His Age|Andrew Lang

British Dictionary definitions for stratum

stratum

/ (ˈstrɑːtəm) /

noun plural -ta (-tə) or -tums

(usually plural) any of the distinct layers into which sedimentary rocks are divided

biology a single layer of tissue or cells

a layer of any material, esp one of several parallel layers

a layer of ocean or atmosphere either naturally or arbitrarily demarcated

a level of a social hierarchy that is distinguished according to such criteria as educational achievement or caste status

Derived Forms

stratal, adjective

Word Origin for stratum

C16: via New Latin from Latin: something strewn, from sternere to scatter

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for stratum

stratum

[ strā′təm, străt′əm ]

n. pl. stra•tums

A horizontal layer of material, especially one of several parallel layers arranged one on top of another.

Any of the layers of differentiated tissue forming an anatomical structure.

Related forms

stra′tal (-təl) adj.

Science definitions for stratum

stratum

[ strā′təm, străt′əm ]

Plural strata stratums

A layer of sedimentary rock whose composition is more or less the same throughout and that is visibly different from the rock layers above and below it.

A layer of tissue, as of the skin or another organ.