[ strey-tuh, strat-uh, strah-tuh ]
/ ˈstreɪ tə, ˈstræt ə, ˈstrɑ tə /


a plural of stratum.
(usually considered nonstandard) stratum.



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usage note for strata

See stratum.

Definition for strata (2 of 2)

[ strey-tuh m, strat-uh m ]
/ ˈstreɪ təm, ˈstræt əm /

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

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

usage note for stratum

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.


stra·tous, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for strata

British Dictionary definitions for strata (1 of 2)

/ (ˈstrɑːtə) /


a plural of stratum

usage for strata

Strata is sometimes wrongly used as a singular noun: this stratum (not strata) of society is often disregarded

British Dictionary definitions for strata (2 of 2)

/ (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 of stratum

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

Medical definitions for strata

[ strātəm, strătəm ]

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.

Other words from stratum

stratal (-təl) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for strata

[ strātəm, strătəm ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.