substratum
/sʌbˈstrɑːtəm
/ /sʌbˈstreɪtəm/noun (plural substrata /sʌbˈstrɑːtə/ /sʌbˈstreɪtə/)
1An underlying layer or substance, in particular a layer of rock or soil beneath the surface of the ground: the plant will grow very rapidly and send out runners above the substratum a geological substratum whole substrata of society...
- Deep drilling in the southern Tyrrhenian Sea floor revealed a continental and oceanic substratum covered by upper Miocene and younger sedimentary successions.
- The acoustic facies of its substratum has neither the characteristics of the continental crust nor those of the oceanic crust.
- Paleocene fossil outcrops abound in the glauconite rich gray clay substrata of the creek banks exposed beneath the deep rich surface soils.
1.1A foundation or basis of something: there is a broad substratum of truth in her story...
- The idea that Aboriginal culture is essentially unchanging and thus ‘the oldest in the world’ appeals to many Australians, and presumably strengthens the substratum of support for native title, as well as the Aboriginal art market.
- His materials and settings are drawn from the substratum of his experience as a curator, trained in taxidermy, active in the conservation of paintings and the handling of fossils, fascinated by animal maquettes and mediaeval weapons.
- They are part of the range of institutions that have been the substratum of Scottish distinctiveness within the UK.
Origin
Mid 17th century: modern Latin, neuter past participle (used as a noun) of Latin substernere, from sub- 'below' + sternere 'strew'. Compare with stratum.