What do you mean by flank?

The famous mouth side means the following:

The word "famous mouth flank" is quite common in the political context of Taiwan Province Province. It is usually used to describe some well-known TV program hosts or commentators, whose opinions and remarks often affect the tendency of public opinion. These people are usually supporters of a political faction, and their speeches and opinions often have obvious tendencies to defend the policies or positions of the political faction. For example, Carolyn, the wife of Taipei Mayor Ke Wenzhe, once said that those who win the media, support the Internet and have wings will win the world. This statement reveals that in the political environment of Taiwan Province Province, the party with media resources, network power and flank support can often occupy the dominant position. Another example is that in a public speech, Ke criticized Hou Youyi for making private letters public, saying that this is what celebrities and flanks are doing, which also reflects the influence of celebrities and flanks in the political environment of Taiwan Province.