(philosophy) that which is; an entity, a being, an existent

plural of essent

Necessary. / Very important; of high importance. / (biology) Necessary for survival but not synthesized by the organism, thus needing to be ingested. / Being in the basic form; showing its essence.

A necessary ingredient. / A fundamental ingredient.

(biochemistry) One of the nine naturally occurring amino acids that the human body cannot synthesize, and so must be provided by dietary protein.

in essence

A volatile oil, used to make perfumes and flavourings, especially one having the characteristic odour of the plant from which it is obtained.

(biochemistry) any fatty acid required for human metabolism that cannot be synthesized by the body and must be present in the diet; originally designated as vitamin F

(nutrition) A compound that must be obtained from food for survival

plural of essential