absolutely necessary; indispensable: Discipline is essential in an army.
pertaining to or constituting the essence of a thing.
noting or containing an essence of a plant, drug, etc.
being such by its very nature or in the highest sense; natural; spontaneous: essential happiness.
  1. (of a singularity of a function of a complex variable) noting that the Laurent series at the point has an infinite number of terms with negative powers.
  2. (of a discontinuity) noting that the function is discontinuous and has no limit at the point.Compare removable(def 2).


a basic, indispensable, or necessary element; chief point: Concentrate on essentials rather than details.

Origin of essential

1300–50; Middle English essencial < Medieval Latin essenciālis for Late Latin essentiālis. See essence, -al1
Related formses·sen·tial·ly, adverbes·sen·tial·ness, nounpre·es·sen·tial, noun, adjectivepre·es·sen·tial·ly, adverbqua·si-es·sen·tial, adjectivequa·si-es·sen·tial·ly, adverbsub·es·sen·tial, adjectivesub·es·sen·tial·ly, adverbsub·es·sen·tial·ness, noun

Synonyms for essential

1. fundamental, basic, inherent, intrinsic, vital. See necessary. 2. Essential, inherent, intrinsic refer to that which is in the natural composition of a thing. Essential suggests that which is in the very essence or constitution of a thing: Oxygen and hydrogen are essential in water. Inherent means inborn or fixed from the beginning as a permanent quality or constituent of a thing: properties inherent in iron. Intrinsic implies belonging to the nature of a thing itself, and comprised within it, without regard to external considerations or accidentally added properties: the intrinsic value of diamonds.

Antonyms for essential Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for essentially

Contemporary Examples of essentially

Historical Examples of essentially

British Dictionary definitions for essentially



in a fundamental or basic way; in essence



vitally important; absolutely necessary
basic; fundamentalthe essential feature
completely realized; absolute; perfectessential beauty
biochem (of an amino acid or a fatty acid) necessary for the normal growth of an organism but not synthesized by the organism and therefore required in the diet
derived from or relating to an extract of a plant, drug, etcan essential oil
logic (of a property) guaranteed by the identity of the subject; necessary. Thus, if having the atomic number 79 is an essential property of gold, nothing can be gold unless it has that atomic number
music denoting or relating to a note that belongs to the fundamental harmony of a chord or piece
pathol (of a disease) having no obvious external causeessential hypertension
geology (of a mineral constituent of a rock) necessary for defining the classification of a rock. Its absence alters the rock's name and classification


something fundamental or indispensablea sharp eye is an essential for a printer
music an essential note
Derived Formsessentiality (ɪˌsɛnʃɪˈælɪtɪ) or essentialness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for essentially



mid-14c., "that is such by its essence," from Late Latin essentialis, from essentia (see essence). Meaning "pertaining to essence" is from late 14c., that of "constituting the essence of something" is from 1540s; that of "necessary" is from 1520s. Essentials "indispensable elements" is from early 16c. Related: Essentially.

Online Etymology Dictionary, © 2010 Douglas Harper

essentially in Medicine




Constituting or being part of the essence of something; inherent.
Basic or indispensable; necessary.
Of, relating to, or being a dysfunctional condition or a disease whose cause is unknown.
Of, relating to, or being a substance that is required for normal functioning but cannot be synthesized by the body and therefore must be included in the diet.


Something fundamental.
Something necessary or indispensable.
Related formses•sen′ti•ali•ty (-shē-ălĭ-tē) null n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.