stratum
1. any of the distinct layers into which sedimentary rocks are divided
2. Biology a single layer of tissue or cells
3. a layer of ocean or atmosphere either naturally or arbitrarily demarcated
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
stratum
see SOCIAL STRATUM.Collins Dictionary of Sociology, 3rd ed. © HarperCollins Publishers 2000
stratum
[′strad·əm] (geology)
A mass of homogeneous or gradational sedimentary material, either consolidated rock or unconsolidated soil, occurring in a distinct layer and visually separable from other layers above and below.
(science and technology)
One in a sequence of distinct layers.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
stratum
A bed of sedimentary rock or earth.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
Stratum
The next generation of software-defined networking (SDN) from the Open Networking Foundation (ONF). The Stratum project was announced in early 2018 with code from Google's own operations. Whereas the ONF's OpenFlow provides the protocol to instruct the devices, Stratum actually configures and controls the forwarding. See OpenFlow.Copyright © 1981-2025 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
Stratum
in geology, the principal form of occurrence of sedimentary rocks, reflecting their sequential deposition. A stratum has more or less homogeneous composition and is confined by two roughly parallel surfaces (the upper is the ceiling and the lower is the sole). The thickness of a stratum, from fractions of a meter to several meters, is much less than the length. Each stratum (with normal, undisturbed bedding) is younger than the one beneath it. Strata may also be composed of metamorphic rocks. Magmatic rocks and ores that are stratiform are called sheet deposits.
Stratum
a designation for social levels or classes found in certain non-Marxist conceptions of social stratification.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.