Pronunciation: (es'uns),[key] —n. 1. the basic, real, and invariable nature of a thing or its significant individual feature or features: Freedom is the very essence of our democracy. 2. a substance obtained from a plant, drug, or the like, by distillation, infusion, etc., and containing its characteristic properties in concentrated form.
3. an alcoholic solution of an essential oil; spirit.
4. a perfume; scent.
5. Philos.the inward nature, true substance, or constitution of anything, as opposed to what is accidental, phenomenal, illusory, etc.
6. something that exists, esp. a spiritual or immaterial entity.
7. in essence, essentially; at bottom, often despite appearances: For all his bluster, he is in essence a shy person. 8. of the essence, absolutely essential; critical; crucial: In chess, cool nerves are of the essence.