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sub·stra·tum

(sŭbstrā′təm, -străt′əm)

n. pl. sub·stra·ta(-strā′tə, -străt′ə) or sub·stra·tums

a. An underlying layer.

b. A layer of earth beneath the surface soil; subsoil.

2. A foundation or groundwork.

3. The material on which another material is coated or fabricated.

4. Philosophy The underlying characterless substance that supports attributes of material reality.

5. Biology A substrate.

6. Linguistics A substrate.

[New Latin substrātum, from neuter of Latin substrātus, past participle of substernere, to lay under : sub-, sub- + sternere, to stretch, spread; see ster-² in the Appendix of Indo-European roots.]

sub·strative adj.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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