Origin and history of essence

late 14c., essencia, essencie (respelled late 15c. on French model), in philosophy, "true being, substance," as distinguished from accidental qualities or appearances, from Latin essentia "being, essence," abstract noun formed (to translate Greek ousia "being, essence") from essent-, present participle stem of esse "to be," which is reconstructed to be from PIE root *es- "to be."

Originally in English in reference to the substance of the Trinity; the general sense of "basic element of anything" is attested by 1650s, though this is the underlying notion of the Middle English use of essential.

The meaning "ingredient which gives something its particular character" is from c. 1600, especially in reference to distilled oils from plants (1650s), hence "fragrance, perfume" (17c.). In 19c. U.S., essence-peddler could mean "medical salesman" and "skunk."

Essence, in its primary signification, means the principle of individuation, the inmost principle of the possibility of any thing, as that particular thing. [Coleridge, "Biographia Literaria"]