What does "irritant" mean?

Irritant: That which irritates or excites.

Additional senses

  1. 2.(Physiol. & Med.) Any agent by which irritation is produced; as, a chemical irritant; a mechanical or electrical irritant.
  2. 3.(Toxicology) A poison that produces inflammation. Counter irritant. See under Counter. -- Pure irritant (Toxicology), a poison that produces inflammation without any corrosive action upon the tissues.

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