Definition of Capsule

Capsule: Capsule has many meanings in medicine including the following:

  1. In medicine, a membranous structure that envelops an organ, a joint, tumor, or any other part of the body. It is usually made up of dense collagen-containing connective tissue.
  2. In pharmacy, a solid dosage form in which the drug is enclosed in a hard or soft soluble container, usually of a form of gelatin.
  3. In microbiology, a coat around a microbe, such as a bacterium or fungus.

Derived from the diminutive of the Latin word "capsa" meaning "box", a capsule is literally "a little box" and can refer to any encompassing structure or small container.


Last Editorial Review: 6/14/2012

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