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1610s, from Modern Latin stratificationem (nominative stratificatio), noun of action from past participle stem of stratificare "to form strata," from stratum "thing spread out" + root of facere "to make" (see factitious).
stratification strat·i·fi·ca·tion (strāt'ə-fĭ-kā'shən)
An arrangement in layers or strata.
The process by which materials form or are deposited in layers, as in sedimentary rocks and some igneous rocks.
Note: The atmosphere and the ocean also exhibit stratification, with the warmer air or water occupying the upper layers.