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Stratum Definition & Meaning - Merriam-Webster
STRATUM Definition & Meaning | Dictionary.com
STRATUM | definition in the Cambridge English Dictionary
STRATUM | English meaning - Cambridge Dictionary
Stratum - Definition, Meaning & Synonyms | Vocabulary.com
STRATUM definition and meaning | Collins English Dictionary
STRATUM Definition & Usage Examples | Dictionary.com
stratum noun - Definition, pictures, pronunciation and usage …
Stratum - definition of stratum by The Free Dictionary
Stratum - Wikipedia