Language: Dzongkha
Churi chenm literally means "wavy pattern". It describes a certain type of Bhutanese sword (patag), referring to a triple "W" pattern on its silver-clad scabbard. The pattern resembles a splashing and meandering river.
Swords with the churi chenm scabbard were traditionally worn by the king himself and senior officials like his changap or chief attendant.


A Bhutanese sword with churi chenm scabbard.
Sources of term
Phuntsho Rapten (Researcher at the Centre for Bhutan Studies, Thimphu):
"It has a silver scabbard and three layers of churi design in the middle. Hence the name churi chenm. The churi design is gold plated. This is considered one of the best scabbards. Although the changa of the king particularly wore it in olden days, many high officials today wear it during important occasions. Gongsar Ugyen Wangchuck wore it as is evident from his earlier group picture."1
Dr. Jagar Dorji:
"Churi chenm (wavy pattern) - the sword has scabbard of silver showing the meanders of a river in the middle. It is gold plated. Churi chenm is considered the best scabbard that senior officials wear."
Notes
1. Phuntsho Rapten (Researcher at the Centre for Bhutan Studies, Thimphu) Patag, the symbol of heroes.
2. Dr. Jagar Dorji, Intangible Cultural Heritage of Bhutan. Research & Media Division. National Library & Archives of Bhutan. Published auspices of UNESCO. Page 225. (Available online.)

Jigme Singye Wangchuck, the fourth king of Bhutan, ruled 1972 - 2006, with his churi chenm style sword in 1992.

Sir Ugyen Wangchuck during the Younghusband expedition to Tibet in 1904, before he became a king.
He already carries a silver scabbard patag but unfortunately, the mid-section is obscured.

Sir Ugyen Wangchuck on a 1907 state visit to Calcutta. Next to him, in the middle of the picture, is Sir John Claude White. This may be the picture that Phuntsho Rapten is referring to, since it is the only one that does show the scabbard. I have not been able to find a higher resolution of this image to verify whether he is in fact wearing the churi chenm decorated patag