stratum

noun plural strata, (C)

1 a layer of rock of a particular kind, especially one with different layers above and below it

2 a layer of earth, such as one where tools, bones etc from an ancient civilization are found by digging

3 a social class in a society

straw, noun 1

a) (U) the dried stems of wheat or similar plants that are used for animals to sleep on, and for making things such as baskets, mats etc: a straw hat

b) (C) a single dried stem of wheat etc: Some straws were sticking to his jacket.

2 (C) a thin tube of paper or plastic for sucking up liquid: a boy happily drinking a chocolate milkshake through a straw

3 the last straw/the straw that breaks the camel's back the last problem in a series of problems that finally makes you give up, get angry etc

4 a straw in the wind BrE a sign of what might happen in the future: These stories of food riots may well be straws in the wind.

5 straw man AmE a weak opponent or imaginary argument that can easily be defeated

—see also: you can't make bricks without straw brick 1 (4), clutch at straws clutch 1, draw the short straw draw 1 (26)