essential

Less common meanings

6. 6
   no known causeadjective

   Of a disease or condition, arising from no identifiable cause.

   Essential blepharospasm, in which the eyelids clamp shut against the patient's will, has no identifiable underlying cause.

   He was diagnosed with essential hypertension after other causes were ruled out.

   UsageComes right before the name of the condition: essential tremor, essential hypertension.

   Similaridiopathic, primary

   Oppositesecondary

   Note

   It means the same as idiopathic, and doctors use it when no underlying cause can be identified. Here it never suggests that the condition is needed or important.

7. 7
   pure spiritadjective

   Having the nature of pure essence rather than physical substance; non-material.

   Similarimmaterial, spiritual, incorporeal

   Oppositematerial, physical

   Note

   Where the "really existing" sense says that something is, this one says what kind of thing it is: essence rather than matter. In Arthur Conan Doyle's The Land of Mist (1926), a clergyman describes the natural body, which dies, and the spiritual body that survives, then says, "Those are the essential things." Because he means both bodies, the "most important" reading fits there at least as well. Source

   Checked 6 Nov 2026 · 3 facts

   • The Conan Doyle work containing this quotation dates from 1925–1926. gutenberg.net.au
   • The words “the essential things” occur in Arthur Conan Doyle's writing. gutenberg.net.au
   • The speaker is the fictional Rev. Charles Mason in The Land of Mist, chapter VIII. His statement follows a description of both the natural body and the spiritual body; it does not unambiguously exemplify the non-material sense. gutenberg.net.au
8. 8
   adjectivearchaic

   Actually existing in reality rather than only imagined; real.

   Or is it true, that thou art but a bare name, / And no eſſential thing?

   1612, John Webster, The Tragedy of the Dutchesse of Malfy.

   Similarexisting, existent

   Oppositeimaginary

   Note

   Real existence is the plainest echo of Latin essentia, "being." John Webster's The Duchess of Malfi (1612–1613) sets it against mere naming: "thou art but a bare name, / And no essential thing?" Modern readers tend to hear "necessary" first, so this sense needs a clear contrast to come through, such as name against thing or real against imagined. Source

   Checked 6 Nov 2026 · 3 facts

   • Essential ultimately derives from Latin essentia, meaning “being” or “essence.” en.wiktionary.org
   • John Webster wrote The Duchess of Malfi in 1612–1613; these are writing dates, not publication dates. corpus.cam.ac.uk
   • The quoted words occur in the play, spoken by Ferdinand as he questions whether virtue has real existence. extra.shu.ac.uk
9. 9
   adjective

   Of a lamination of a 3-manifold, having every complementary region irreducible, every region boundary incompressible by disks and monogons, and no leaf a sphere or a torus bounding a solid torus in the manifold.