What does "insensible" mean?

Insensible: Not susceptible of emotion or passion; void of feeling; apathetic; unconcerned; indifferent; as, insensible to danger, fear, love, etc.; -- often used with of or to. Accept an obligation without being a slave to the giver, or insensible to his kindness. Sir H. Wotton. Lost in their loves, insensible of shame. Dryden.

Additional senses

  1. 2.Incapable of being perceived by the senses; imperceptible. Hence: Progressing by imperceptible degrees; slow; gradual; as, insensible motion. Two small and almost insensible pricks were found upon Cleopatra's arm. Sir T. Browne. They fall away, And languish with insensible decay. Dryden.
  2. 3.Not sensible or reasonable; meaningless. [Obs.] If it make the indictment be insensible or uncertain, it shall be quashed. Sir M. Hale.

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