The phrase "western flank" refers to the western side or edge of something. It can be used to describe the western part or area of a country, a military operation, or an organization. Full definition
Remember the 1961 plebiscite, in which the Anglophone south - western flank of Cameroon voted to join the Francophone majority to the east and north, while the northern tract of the same English - administered territory opted to stay, as Nigeria's Sardauna Province? (nigeriapoliticsonline.com)
And these trends are in addition to the persistent dangers posed by the North Korean regime, and the instabilities on Asia's Western flank in Afghanistan and Pakistan. (asiapacific.ca)
Although losses are partly offset by strong gains on the spine and western flank of the Antarctic Peninsula, numerous glaciers feeding intact Antarctic Peninsula, West Antarctic and East Antarctic ice shelves are also thinning dynamically. (thinkprogress.org)