NOUN (2)

1. enforced isolation of patients suffering from a contagious disease in order to prevent the spread of disease;

2. isolation to prevent the spread of infectious disease;


VERB (1)

1. place into enforced isolation, as for medical reasons;
- Example: "My dog was quarantined before he could live in England"

The Collaborative International Dictionary of English v.0.48:

Quarantine \Quar`an*tine"\, v. t. [imp. & p. p. Quarantined;
   p. pr. & vb. n. Quarantining.]
   To compel to remain at a distance, or in a given place,
   without intercourse, when suspected of having contagious
   disease; to put under, or in, quarantine.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Quarantine \Quar"an*tine\, n. [F. quarantaine, OF. quaranteine,
   fr. F. quarante forty, L. quadraginta, akin to quattuor four,
   and E. four: cf. It. quarantina, quarentine. See Four, and
   cf. Quadragesima.]
   1. A space of forty days; -- used of Lent.
      [1913 Webster]

   2. Specifically, the term, originally of forty days, during
      which a ship arriving in port, and suspected of being
      infected a malignant contagious disease, is obliged to
      forbear all intercourse with the shore; hence, such
      restraint or inhibition of intercourse; also, the place
      where infected or prohibited vessels are stationed.
      [1913 Webster]

   Note: Quarantine is now applied also to any forced stoppage
         of travel or communication on account of malignant
         contagious disease, on land as well as by sea.
         [1913 Webster]

   3. (Eng. Law) The period of forty days during which the widow
      had the privilege of remaining in the mansion house of
      which her husband died seized.
      [1913 Webster]

   Quarantine flag, a yellow flag hoisted at the fore of a
      vessel or hung from a building, to give warning of an
      infectious disease; -- called also the yellow jack, and
      yellow flag.
      [1913 Webster]

WordNet (r) 3.0 (2006):

quarantine
    n 1: enforced isolation of patients suffering from a contagious
         disease in order to prevent the spread of disease
    2: isolation to prevent the spread of infectious disease
    v 1: place into enforced isolation, as for medical reasons; "My
         dog was quarantined before he could live in England"