ˈstrɑ:təm n. (pl. strata) 1
esp. Geol. a
layer or set of
successive layers of
any deposited
substance. 2 an atmospheric layer. 3 a layer of
tissue etc. 4 a a
social grade,
class, etc. (the
various strata of society). b
Statistics each of
the groups
into which a
population is divided in stratified
sampling. øøstratal adj. [L, =
something spread or
laid down, neut.
past part. of sternere strew]