Other forms: strata
A stratum is one layer, of rock or of society. A stratum of clay, every social stratum.
In rock each stratum is older than the one above, which is how time is read from a cliff. The plural is strata, and a stratum is one of them however often people forget.
1nounstratumOne layer, of rock or of society.
“The dark stratum was volcanic ash from a single year.”
stratum is a layer.
Latin stratum, something spread out, from sternere, to spread; the same root gives street.
Proto-Indo-European
*sterh₃-
Latin
strātum — a spread for a bed, coverlet, quilt, blanket; a pillow, bolster; a bed
English, today
stratum
Built from
Latin strātum (“a spread for a bed, coverlet, quilt, blanket; a pillow, bolster; a bed”), neuter singular of strātus, perfect passive participle of sternō (“spread”). a doublet of estrade and street.
Etymology from Wiktionary, CC BY-SA