A cute story I thought I'd share. My friend heard this when he was using the urinal at his school. Some of his students pointed and said 양근. He couldn't stop laughing.

양근 (yang-geun)

We originally thought it meant foreigner penis. 양 would be the Chinese character 洋 which means foreign. 근 comes from 남근, which is another word for penis. We were wrong. This 양 relates to masculinity. So it is just another word for penis. ㅋㅋㅋ