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Abnormal, excessive irritability.

In med., a state of irritation or excitement of a part, different from, or short of, the inflammatory condition, although often passing into it; unnatural energy of action.

Augmentation of the vital phenomena in any organ or tissue. Orgasm. Under this name, Mr. Pearson has described a state of the constitution produced by mercury acting on it as a poison. He calls it Mercurial Erethism or Erethismus. It is characterized by great depression of strength; anxiety about the praecordia; irregular action of the heart; frequent sighing; tremors; small, quick, sometimes intermitting pulse; occasional vomiting; pale, contracted countenance, and sense of coldness; but the tongue is seldom furred, nor are the vital and natural functions much disturbed. In this state any sudden exertion may prove fatal.

Morbid excitability.

Excitement of an organ or tissue in an unusual degree, also over-excitement of the passions or mental emotions. [Gr.]