What does "kwukyel" mean in regards to Chinese language characters? My Pleco always tells me two little hashes on the top of 汉字 such as. 

兑

are "kwukyel".  

Can anyone point me to a reference that explains this term as it relates to Chinese language?



ps --  I already know the explanation about older Korean. That is not the question.  

I'm asking about why this is in my Chinese language dictionaries (at least two).   

[ -- this premise is not quite correct ----
 I don't believe these dictionaries are intended to be abstract Hanzi references.] 

They are Chinese language dictionaries.  


Is there any good reference that explains the mapping to "kwukyel"
for Chinese language is wrong?  
If the term "kwukyel" is not meaningful for Chinese language, what definition should the marks be mapped to?


If the answer is "nothing", please provide some evidence/references so I can give credit to your answer. :-)
kwukyel or gugyeol is a Korean system to write Chinese characters phonetically that predates Hangul. As for 丷 itself, to quote from Wiktionary: 


  This is a kwukyel note. Kwukyel was a system formerly used in Korea whereby correct interpretation of texts written in Classical Chinese was aided by small interspersed notes such as this one. The notes represent Korean morphemes but were only used within Chinese text.