different between dullness vs torpidity

English

From dull +? -ness.

dullness (usually uncountable, plural dullnesses)

The quality of being slow of understanding things; stupidity.
The quality of being uninteresting; boring or irksome.
Lack of interest or excitement.
The lack of visual brilliance; want of sheen.
(of an edge) bluntness.
The quality of not perceiving or kenning things distinctly.
(archaic) Drowsiness.
- c. 1610-11, William Shakespeare, The Tempest, Act I scene ii^[1]:
  Prospero: […] Thou art inclin'd to sleep. 'Tis a good dulness, / And give it way— I know thou canst not choose.

torpid +? -ity

torpidity (countable and uncountable, plural torpidities)

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