cordon sanitaire
noun
cor·don sa·ni·taire kȯr-ˌdōⁿ-sä-nē-ˈter 
: a protective barrier (as of buffer states) against a potentially aggressive nation or a dangerous influence (such as an ideology)
Example Sentences
Recent Examples on the Web Indeed, the very fact that the U.S. is sending troops to Romania and Poland, creating in effect a cordon sanitaire, shows that Biden is far more concerned about spillover from a war in Ukraine than Ukraine itself. 
Michael A. Cohen, The New Republic, 11 Feb. 2022 But no law requires that people fleeing political violence and natural disaster should be met by the militarized cordon sanitaire in South Texas. Alicia Schmidt Camacho, The New Yorker, 19 Jan. 2022 Ron Trewyn told us of one sheriff—the exception, rather than the rule—who had mapped the optimal locations for the 40 roadblocks needed to create a cordon sanitaire, quarantining his entire county in the event of an outbreak. Nicola Twille, Wired, 6 July 2021 Plum Island has the advantage of a natural cordon sanitaire—the ocean. Nicola Twille, Wired, 6 July 2021 It was confidently assumed that coffee rust could not cross the cordon sanitaire of the Atlantic. Maryn Mckenna, The Atlantic, 16 Sep. 2020 The cordon sanitaire around Eyam was similar to controls imposed by local magistrates on a number of parishes and villages in the 1660s. 1843, 16 Apr. 2020 The cordon sanitaire that began around Wuhan and two nearby cities on Jan. 23 helped slow the virus’s... Jeremy Page, WSJ, 24 Mar. 2020 Authorities have imposed a cordon sanitaire, limiting movement into and out of the country and between cities and towns, except for those going to work or in emergencies. Annysa Johnson, Milwaukee Journal Sentinel, 20 Mar. 2020 See More
Michael A. Cohen, The New Republic, 11 Feb. 2022 But no law requires that people fleeing political violence and natural disaster should be met by the militarized cordon sanitaire in South Texas. Alicia Schmidt Camacho, The New Yorker, 19 Jan. 2022 Ron Trewyn told us of one sheriff—the exception, rather than the rule—who had mapped the optimal locations for the 40 roadblocks needed to create a cordon sanitaire, quarantining his entire county in the event of an outbreak. Nicola Twille, Wired, 6 July 2021 Plum Island has the advantage of a natural cordon sanitaire—the ocean. Nicola Twille, Wired, 6 July 2021 It was confidently assumed that coffee rust could not cross the cordon sanitaire of the Atlantic. Maryn Mckenna, The Atlantic, 16 Sep. 2020 The cordon sanitaire around Eyam was similar to controls imposed by local magistrates on a number of parishes and villages in the 1660s. 1843, 16 Apr. 2020 The cordon sanitaire that began around Wuhan and two nearby cities on Jan. 23 helped slow the virus’s... Jeremy Page, WSJ, 24 Mar. 2020 Authorities have imposed a cordon sanitaire, limiting movement into and out of the country and between cities and towns, except for those going to work or in emergencies. Annysa Johnson, Milwaukee Journal Sentinel, 20 Mar. 2020 See More Word History
Etymology
borrowed from French, literally, "sanitary cordon," originally in reference to a line of military posts or other barriers enclosing a community stricken by an infectious disease
First Known Use
1920, in the meaning defined above