Stratum
/ˈstreɪ.təm/noun
A layer of material, especially one of several different layers in rock, soil, or sediment.
Did you know?Stratum comes from Latin *stratum*, the past participle used as a noun from *sternere* (“to spread out, strew”), the same root behind *street*, *strew*, and *stretcher*—a root of laying things down, physically and symbolically.
Etymological Timeline
Proto-Indo-European
PIE
*stere-
“to spread, stretch, lay flat”
Latin
Latin
sternere
“to spread out, strew, lay low”
Classical Latin
Latin
stratum
“something spread out; a bed, covering, layer”
Late Latin / Medieval Latin
Latin
stratum
“a layer or bed of material”
14th-16th Century
English
stratum
“a layer or bed, especially of rock or earth”
Modern English
English
stratum
“one of several distinct layers or levels”