Adjective

(en adjective)

Necessary.

Very important; of high importance.

* {{quote-magazine, date=2013-05-17

, author=George Monbiot, authorlink=George Monbiot , title=Money just makes the rich suffer , volume=188, issue=23, page=19 , magazine=(The Guardian Weekly) citation , passage=In order to grant the rich these pleasures, the social contract is reconfigured. The welfare state is dismantled. Essential public services are cut so that the rich may pay less tax. […]}}

Being in the basic form; showing its essence.

Don’t mind him being grumpy. That’s the essential Fred.

Really existing; existent.

* Webster (1623)

Is it true, that thou art but a name, / And no essential thing?

Such 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.

(medicine) Idiopathic.

Adjective

(en adjective)

(literally) Excluding items or members that do not meet certain conditions.

(figuratively) Referring to a membership organisation, service or product: of high quality and/or reknown, for superior members only. A snobbish usage, suggesting that members who do not meet requirements, which may be financial, of celebrity, religion, skin colour etc., are excluded.

Exclusive''' clubs tend to serve ' exclusive brands of food and drinks, in the same exorbitant price range, such as the 'finest' French châteaux.

exclusionary

whole, undivided, entire

''The teacher's pet commands the teacher's exclusive attention.