essential(n = noun.object) necessary, necessity, requirement, requisite - anything indispensable; "food and shelter are necessities of life"; "the essentials of the good life"; "allow farmers to buy their requirements under favorable conditions"; "a place where the requisites of water fuel and fodder can be obtained"
is a kind of thing
has particulars: desideratum, must, need, want
Antonym: inessential
Derived form adjective essential₁

1.  essential(s = adj.all) indispensable - absolutely necessary; vitally necessary; "essential tools and materials"; "funds essential to the completion of the project"; "an indispensable worker"
Derived forms noun essential₁, noun essentialness₁

2.  essential(a = adj.all) - basic and fundamental; "the essential feature"
Antonym: inessential
Derived forms noun essentiality₁, noun essentialness₁

3.  essential(s = adj.all) all important, all-important, crucial, of the essence - of the greatest importance; "the all-important subject of disarmament"; "crucial information"; "in chess cool nerves are of the essence"
Derived forms noun essence₁, noun essentiality₁, noun essentialness₁

4.  essential(a = adj.pert) - being or relating to or containing the essence of a plant etc; "essential oil"
Derived forms noun essence₂, noun essentialness₁

5.  essential(a = adj.all) substantive - defining rights and duties as opposed to giving the rules by which rights and duties are established; "substantive law"
Derived form noun essentialness₁

1.  Belonging to the essence, or that which makes an object, or class of objects, what it is. [1913 Webster]
"Majestic as the voice sometimes became, there was forever in it an essential character of plaintiveness." [1913 Webster]

2.  Hence, really existing; existent. [1913 Webster]
"Is it true, that thou art but a name,
And no essential thing?" [1913 Webster]

3.  Important in the highest degree; indispensable to the attainment of an object; indispensably necessary. [1913 Webster]
"Judgment's more essential to a general
Than courage." [1913 Webster]
"How to live? -- that is the essential question for us." [1913 Webster]

4.  Containing the essence or characteristic portion of a substance, as of a plant; highly rectified; pure; hence, unmixed; as, an essential oil. Ford. [1913 Webster]

5.  Necessary; indispensable; -- said of those tones which constitute a chord, in distinction from ornamental or passing tones. [1913 Webster]

6.  Idiopathic; independent of other diseases. [1913 Webster]

1.  Existence; being. Milton. [1913 Webster]

2.  That which is essential; first or constituent principle; as, the essentials of religion. [1913 Webster]

essential, adj. & n.
--adj.
1 absolutely necessary; indispensable.
2 fundamental, basic.
3 of or constituting the essence of a person or thing.
4 (of a disease) with no known external stimulus or cause; idiopathic.
--n. (esp. in pl.) a basic or indispensable element or thing.

Idiom:
essential element any of various elements required by living organisms for normal growth. essential oil a volatile oil derived from a plant etc. with its characteristic odour.

Derivative:
essentiality n. essentially adv. essentialness n.

Etymology:
ME f. LL essentialis (as ESSENCE)

N  existence, being, entity, ens, esse, subsistence, reality, actuality, positiveness, fact, matter of fact, sober reality, truth, actual existence, presence, coexistence, stubborn fact, hard fact, not a dream, no joke, center of life, essence, inmost nature, inner reality, vital principle, ontology, existing, existent, under the sun, in existence, extant, afloat, afoot, on foot, current, prevalent, undestroyed, real, actual, positive, absolute, true, substantial, substantive, self-existing, self-existent, essential, well-founded, well-grounded, unideal, unimagined, not potential, authentic, actually, in fact, in point of fact, in reality, indeed, de facto, ipso facto, ens rationis, ergo sum cogito, thinkest thou existence doth depend on time?.

N  intrinsicality, inbeing, inherence, inhesion, subjectiveness, ego, egohood, essence, noumenon, essentialness, essential part, quintessence, incarnation, quiddity, gist, pith, marrow, core, sap, lifeblood, backbone, heart, soul, important part, principle, nature, constitution, character, type, quality, crasis, diathesis, habit, temper, temperament, spirit, humor, grain, disposition, endowment, capacity, capability, moods, declensions, features, aspects, peculiarities, idiosyncrasy, oddity, idiocrasy, diagnostics, derived from within, subjective, intrinsic, intrinsical, fundamental, normal, implanted, inherent, essential, natural, innate, inborn, inbred, ingrained, inwrought, coeval with birth, genetous, haematobious, syngenic, radical, incarnate, thoroughbred, hereditary, inherited, immanent, congenital, congenite, connate, running in the blood, ingenerate, ingenite, indigenous, in the grain, bred in the bone, instinctive, inward, internal, to the manner born, virtual, characteristic, invariable, incurable, incorrigible, ineradicable, fixed, intrinsically, at bottom, in the main, in effect, practically, virtually, substantially, au fond, fairly, character is higher than intellect, come give us a taste of your quality, magnos homines virtute metimur non fortuna, non numero haec judicantur sed pondere, vital spark of heavenly flame.

N  requirement, need, wants, necessities, necessaries, necessaries of life, stress, exigency, pinch, sine qua non, matter of necessity, case of need, case of life or death, needfulness, essentiality, necessity, indispensability, urgency, requisition, run upon, demand, call for, charge, claim, command, injunction, mandate, order, precept, desideratum, want, Adj, required, requisite, needful, necessary, imperative, essential, indispensable, prerequisite, called for, in demand, in request, urgent, exigent, pressing, instant, crying, absorbing, in want of, destitute of, ex necessitate rei, of necessity, there is no time to lose, it cannot be spared, it cannot be dispensed with, mendacem memorem esse oportet, necessitas non habet legem, nec tecum possum trivere nec sine te.

N  importance, consequence, moment, prominence, consideration, mark, materialness, import, significance, concern, emphasis, interest, greatness, superiority, notability, weight, value, usefulness, gravity, seriousness, solemnity, no joke, no laughing matter, pressure, urgency, stress, matter of life and death, memorabilia, notabilia, great doings, red-letter day, great thing, great point, main chance, the be all and the end all, cardinal point, substance, gist, sum and substance, gravamen, head and front, important part, principal part, prominent part, essential part, half the battle, sine qua non, breath of one's nostrils, cream, salt, core, kernel, heart, nucleus, keynote, keystone, corner stone, trump card, salient points, top sawyer, first fiddle, prima donna, chief, triton among the minnows, 'it', important, of importance, momentous, material, to the point, not to be overlooked, not to be despised, not to be sneezed at, egregious, weighty, of note, notable, prominent, salient, signal, memorable, remarkable, unforgettable, worthy of remark, worthy of notice, never to be forgotten, stirring, eventful, grave, serious, earnest, noble, grand, solemn, impressive, commanding, imposing, urgent, pressing, critical, instant, paramount, essential, vital, all-absorbing, radical, cardinal, chief, main, prime, primary, principal, leading, capital, foremost, overruling, of vital importance in the front rank, first-rate, superior, considerable, marked, rare, significant, telling, trenchant, emphatic, pregnant, tanti, materially, in the main, above all, kat' exochin, par excellence, to crown all, to beat all, expende Hannibalem!.

N  greatness, magnitude, size, multitude, immensity, enormity, infinity, might, strength, intensity, fullness, importance, great quantity, quantity, deal, power, sight, pot, volume, world, mass, heap, stock, peck, bushel, load, cargo, cartload, wagonload, shipload, flood, spring tide, abundance, principal part, chief part, main part, greater part, major part, best part, essential part, bulk, mass, great, greater, large, considerable, fair, above par, big, huge, Herculean, cyclopean, ample, abundant, full, intense, strong, sound, passing, heavy, plenary, deep, high, signal, at its height, in the zenith, world-wide, widespread, far-famed, extensive, wholesale, many, goodly, noble, precious, mighty, sad, grave, heavy, serious, far gone, arrant, downright, utter, uttermost, crass, gross, arch, profound, intense, consummate, rank, uninitiated, red-hot, desperate, glaring, flagrant, stark staring, thorough-paced, thoroughgoing, roaring, thumping, extraordinary, important, unsurpassed, complete, august, grand, dignified, sublime, majestic, vast, immense, enormous, extreme, inordinate, excessive, extravagant, exorbitant, outrageous, preposterous, unconscionable, swinging, monstrous, overgrown, towering, stupendous, prodigious, astonishing, incredible, marvelous, unlimited, unapproachable, unutterable, indescribable, ineffable, unspeakable, inexpressible, beyond expression, fabulous, undiminished, unabated, unreduced, unrestricted, absolute, positive, stark, decided, unequivocal, essential, perfect, finished, remarkable, of mark, marked, pointed, veriest, noteworthy, renowned, truly, decidedly, unequivocally, purely, absolutely, seriously, essentially, fundamentally, radically, downright, in all conscience, for the most part, in the main, entirely, abundantly, widely, far and wide, greatly, much, muckle, well, indeed, very, very much, a deal, no end of, most, not a little, pretty, pretty well, enough, in a great measure, richly, to a large extent, to a great extent, to a gigantic extent, on a large scale, so, never so, ever so, ever so dole, scrap, shred, tag, splinter, rag, much, by wholesale, mighty, powerfully, with a witness, ultra, in the extreme, extremely, exceedingly, intensely, exquisitely, acutely, indefinitely, immeasurably, beyond compare, beyond comparison, beyond measure, beyond all bounds, incalculably, infinitely, preeminently, superlatively, immoderately, monstrously, preposterously, inordinately, exorbitantly, excessively, enormously, out of all proportion, with a vengeance, particularly, remarkably, singularly, curiously, uncommonly, unusually, peculiarly, notably, signally, strikingly, pointedly, mainly, chiefly, famously, egregiously, prominently, glaringly, emphatically, kat exochin, strangely, wonderfully, amazingly, surprisingly, astonishingly, incredibly, marvelously, awfully, stupendously, peculiarly, furiously, severely, desperately, tremendously, extravagantly, confoundedly, deucedly, devilishly, with a vengeance, a outrance, a toute outrance, painfully, sadly, grossly, sorely, bitterly, piteously, grievously, miserably, cruelly, woefully, lamentably, shockingly, frightfully, dreadfully, fearfully, terribly, horribly, a maximis ad minima, greatness knows itself, mightiest powers by deepest calms are fed, minimum decet libere cui multum licet, some are born great, some achieve greatness, and some have greatness thrust upon them.

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