nounpl. stra′ta or -·tums
- a horizontal layer or section of material, esp. any of several lying one upon another; specif.,
- Biol. a layer of tissue
- Geol. a single layer of sedimentary rock
- a section, level, or division, as of the atmosphere or ocean, regarded as like a stratum
- any of the socioeconomic groups of a society as determined by birth, income, education, etc.
Origin of stratumModern Latin from L, a covering, blanket from stratus, past participle of sternere, to spread, stretch out, cover: for Indo-European base see strew