What is "cordon sanitaire"

Cordon \Cor"don\ (k[^o]r"d[o^]n; F. k[^o]r`d[^o]N"), n. [F., fr. corde. See Cord.]

1. A cord or ribbon bestowed or borne as a badge of honor; a broad ribbon, usually worn after the manner of a baldric, constituting a mark of a very high grade in an honorary order. Cf. Grand cordon.

2. The cord worn by a Franciscan friar.
   --Sir E. Sandys.

3. (Fort.) The coping of the scarp wall, which projects beyong the face of the wall a few inches.

4. (Mil.) A line or series of sentinels, or of military posts, inclosing or guarding any place or thing.

5. A rich and ornamental lace or string, used to secure a mantle in some costumes of state.

   Cordon sanitaire (k?r` d?n" s?`n?`t?r") [F., sanitary cordon], a line of troops or military posts around a district infected with disease, to cut off communication, and thus prevent the disease from spreading. Also used figuratively, of a group of neutral states that forms a barrier between two hostile states. [1913 Webster] ||

n. 1 A barrier (physical or administrative) to prevent the spread of disease. 2 (context by extension English) Any barrier to the spread of anything deemed undesirable.

Cordon sanitaire is a French phrase that, literally translated, means "sanitary cordon". It originally denoted a barrier implemented to stop the spread of disease, such as the Black Death. The term has also often been used in English in a metaphorical sense to refer to attempts to prevent the spread of an ideology deemed unwanted or dangerous, such as the containment policy adopted by George F. Kennan against the Soviet Union.