Definition of essential
(Entry 1 of 2)
2a
: of the utmost importance : basic, indispensable, necessary
an essential requirement for admission to college
b
: being a substance that is not synthesized by the body in a quantity sufficient for normal health and growth and that must be obtained from the diet
a vegetable oil rich in essential fatty acids
— see also essential amino acid — compare nonessential sense 2
3
: idiopathic
essential disease essential hypertension
essential
nounDefinition of essential (Entry 2 of 2)
1
: something basic
the essentials of astronomy
2
: something necessary, indispensable, or unavoidable
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Merriam-Webster unabridged
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Time Traveler for essential
The first known use of essential was in the 14th century
See more words from the same century