In South Korea, these are household names -- like all the households

Korean Curling Team

GANGNEUNG, South Korea -- The South Korean women's curling team has an important system. Whenever the team's coach wants to address one of her players, she calls out the player's first initial and last name before delivering her message.

For example, if she wants to address Kim Eun Jung, she shouts for E. Kim. If she wants Kim Seon Yong, she hollers for S. Kim. Kim Kyeong Ae is K. Kim. Kim Yeong Mi is Y. Kim. Kim Chohi is C. Kim.

You get the gist.

"Many foreigners ask us, 'Are you all sisters?'" said the team's coach, whose name is -- wait for it -- Kim Min Jung (also known as M. Kim).

As it happens, two of the team members actually are sisters (K. Kim and Y. Kim), but the rest are not related. They are, however, among the many (many) South Korean competitors at the Pyeongchang Olympics who share the surname Kim. In total, 34 of the 121 athletes -- a full 28 percent -- are Kims.

Add in the next two most popular South Korean names, Lee (13) and Park (9), and nearly half of the entire delegation has one of the three names. By comparison, there are only two Johnsons, one Smith and no Jones among the 241 American athletes here.

"Kim is very common in Korea. We are not confused." Korean curling coach, M. Kim

Understand: This phenomenon is not specific to athletes. According to the 2015 census, the 10 most popular names in South Korea (including Kim, Lee and Park) account for nearly 64 percent of all citizens. On its own, Kim is the surname for about 10 million of the 50 million South Koreans, meaning that, statistically, 1 in 5 South Koreans cheering for the all-Kim team at the Gangneung Curling Center on Thursday were Kims, too.

How did this happen? There are a few factors at work, said Andrew Eungi Kim -- A. Kim? -- who is a professor at Korea University's Graduate School of International Studies. First, having a surname at all in Korea was historically a privilege limited only to the country's nobility, meaning that about half of the population did not have a last name until around the 17th century.

At that point, Prof. Kim said, citizens began adopting surnames for themselves and many selected Kim, Lee or Park because "those names were the most prestigious for having produced large numbers of kings, royalties and other historically significant figures."

While that might sound like a somewhat casual approach, names have great meaning to South Koreans, according to Yumi Moon, who is a professor of history focusing on East Asia at Stanford.

While it's impossible for South Koreans to know if they actually descended from one of the prestigious bloodlines -- or if their ancestors just adopted one of those names -- the pride in names is universal. Moon noted that South Korean women, as a rule, do not change their names when they marry. Many Koreans do change their given names -- there is even a subset of fortune-tellers who specialize in helping uncover a person's luckiest given name -- but, "Changing your surname [which is] inherited from your ancestors is disgraceful, according to the custom of the olden days," Moon said.

That importance of the family name is also why a person's surname is rendered first in South Korea and then followed by his or her given name (so, legendary figure skater Kim Yuna's first name -- in American parlance -- is Yuna, not Kim). That protocol is rooted in the strong concept of collectivism which permeates much of South Korean life. For example, when sending a letter to someone, the address is written so that it proceeds from the largest group to the most specific: province, city, district, street, home number and, finally, the person's name.

Still, there are some allowances that must be made for the glut of similarly named people. To avoid confusion in public settings, Prof. Kim said, South Koreans often add a person's profession to their name with the suffix "-nim" to show respect.

"For example, a reporter with the last name Kim would be addressed as ... Kim Reporternim," Professor Kim said. "Other examples would be Kim Professornim, Kim Prosecutornim, Kim Presidentnim. This title calling is so important that even among friends they typically call each other like [this], particularly if the titles are 'respectable' professions."

In more fluid situations -- say, a doctor's office waiting room -- full names are used, sometimes with the person's profession added.

In recent years, an influx of foreigners who have become citizens in South Korea has led to a rise in the number of surnames here, and Prof. Kim said the number, which was once as few as 300, is now closer to 5,000 -- a spike, to be sure, though Japan has roughly 300,000.

So, for the time being at least, there will continue to almost surely be Kims everywhere one looks, particularly at the curling venue, where Team Kim -- the curling tradition is that a team is named after its leader -- has become used to the questions about whether they are all related.

"Kim is very common in Korea," said the coach, M. Kim. "We are not confused."