Princeton's WordNet

1. necessity, essential, requirement, requisite, necessary(adj)

   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"

2. essential, indispensable(adj)

   absolutely necessary; vitally necessary

   "essential tools and materials"; "funds essential to the completion of the project"; "an indispensable worker"

3. essential(adj)

   basic and fundamental

   "the essential feature"

4. all-important(a), all important(p), crucial, essential, of the essence(p)(adj)

   of the greatest importance

   "the all-important subject of disarmament"; "crucial information"; "in chess cool nerves are of the essence"

5. essential(adj)

   being or relating to or containing the essence of a plant etc

   "essential oil"

6. substantive, essential(adj)

   defining rights and duties as opposed to giving the rules by which rights and duties are established

   "substantive law"

Kernerman English Learner's Dictionary

1. essential(adjective)əˈsɛn ʃəl

   necessary, or very important; = vital

   the essential items you need for a week of camping; Water is essential to life.; It is essential that everyone stays calm.; It is essential to add the ingredients in this order.

2. essentialəˈsɛn ʃəl

   most basic and central; = basic, fundamental

   The essential problem is a lack of good nutrition.

Wiktionary

1. essential(Noun)

   A necessary ingredient.

2. essential(Noun)

   A fundamental ingredient.

3. essential(Adjective)

   Idiopathic.

4. essential(Adjective)

   Necessary.

5. essential(Adjective)

   Very important; of high importance.

6. essential(Adjective)

   Being in the basic form; showing its essence.

   Donu2019t mind him being grumpy. Thatu2019s the essential Fred.

7. essential(Adjective)

   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.

Origin: From essentialis, from essentia.

Webster Dictionary

1. Essential(adj)

   belonging to the essence, or that which makes an object, or class of objects, what it is

2. Essential(adj)

   hence, really existing; existent

3. Essential(adj)

   important in the highest degree; indispensable to the attainment of an object; indispensably necessary

4. Essential(adj)

   containing the essence or characteristic portion of a substance, as of a plant; highly rectified; pure; hence, unmixed; as, an essential oil

5. Essential(adj)

   necessary; indispensable; -- said of those tones which constitute a chord, in distinction from ornamental or passing tones

6. Essential(adj)

   idiopathic; independent of other diseases

• noodsaaklikAfrikaans
• جَوْهَري، أساسيArabic
• същественBulgarian
• essencialPortuguese (BR)
• nezbytnýCzech
• wesentlichGerman
• nødvendig; afgørende; essentielDanish
• ουσιώδης, απαραίτητοςGreek
• esencial, imprescindibleSpanish
• hädavajalikEstonian
• ضروریFarsi
• elintärkeäFinnish
• essentielFrench
• חִיוּנִיHebrew
• आवश्यकHindi
• bitan, vrlo važanCroatian
• lényegesHungarian
• pentingIndonesian
• nauðsynlegurIcelandic
• essenzialeItalian
• 絶対必要なJapanese
• 절대 필요한Korean
• būtinasLithuanian
• būtisks; nepieciešamsLatvian
• pentingMalay
• volstrekt noodzakelijkDutch
• absolutt nødvendig, livsviktigNorwegian
• koniecznyPolish
• ضروریPersian
• ضرورى، اصلى، اساسى،Pashto
• essencialPortuguese
• necesar, esenţialRomanian
• необходимыйRussian
• nevyhnutnýSlovak
• bistvenSlovenian
• neophodanSerbian
• nödvändig, oumbärligSwedish
• จำเป็นThai
• gerekliTurkish
• 必要的Chinese (Trad.)
• істотний; невід'ємнийUkrainian
• نہایت ضروریUrdu
• thiết yếuVietnamese
• 根本的，基本的Chinese (Simp.)