What does "cathartic" mean?

Cathartic: Of or pertaining to the purgative principle of senna, as cathartic acid.

Additional senses

  1. 2.A medicine that promotes alvine discharges; a purge; a purgative of moderate activity. Note: The cathartics are more energetic and certain in action that the laxatives, which simply increase the tendency to alvine evacuation; and less powerful and irritaint that the drastic purges, which cause profuse, repeated, and watery evacuations. -- Ca*thar"tic*al*ly, adv. -- Ca*thar"tic*al*ness, n.

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