English
exosubstance
From exo- + substance.
Proto-Indo-European *h₁eǵʰs ‘out of’
Proto-Hellenic *eks
Ancient Greek ἐκ ‘Out of, from’
Ancient Greek ἔξω ‘outer’
English exo-
Proto-Indo-European *steh₂- ‘to stand (up)’
…
Latin substāns
Latin substantia ‘substance, essence’
Old French substance ‘most essential’
Middle English substance ‘essence’
English substance
Today it means
noun Any substance that is active outside of the cell that produced it
Language periods are conventional ranges, not dates for this word.
Etymograph / exosubstance