Definitionen
1.AdjectiveNecessary.
2.AdjectiveVery important; of high importance.
3.AdjectiveNecessary for survival but not synthesized by the organism, thus needing to be ingested.
4.AdjectiveBeing in the basic form; showing its essence."Don’t mind him being grumpy. That’s the essential Fred."
5.AdjectiveReally existing; existent.
6.AdjectiveSuch that each complementary region is irreducible, the boundary of each complementary region is incompressible by disks and monogons in the complementary region, and no leaf is a sphere or a torus bounding a solid torus in the manifold."(Can we add an example for this sense? (difference between 1 and 2))"
7.AdjectiveIdiopathic."essential blepharospasm"
8.AdjectiveHaving the nature of essence; not physical.
9.NounA necessary ingredient.
10.NounA fundamental ingredient."(Can we add an example for this sense?)"