The most common and most likely answer to this crossword clue is the 6 letter word ETHNIC
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More clues leading to the result ETHNIC
- Niche product ultimately diverted folk
- Race Elizabeth and Nicholas are holding together
- Referring to group’s moral principle, going round North
- Cultural technicality — first half needs sorting
- Code cracked by unspecified number of people in a group
- Cultural Revolution’s end, in principle
- Worried the mostly pleasant folk
- Folk dancing in the capital of China
- Newspaper’s leader has moral code about racial designation
- Exotic event horizon, idyllic on the outside
Buddy explains!

The straight part
We know that "National" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case national = ethnic.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ETHNIC mean?
ETHNIC noun- An ethnic person, especially a foreigner or member of an immigrant community.
- An ethnic minority.
- A heathen, a pagan.
- (in classical scholarship) the demonym of an Ancient Greek city
- Of or relating to a group of people having common racial, ancestral, national, religious or cultural origins.
- Characteristic of a foreign, usually non-Western culture.
- Representative of a folk or traditional mode of expression.
- Heathen, not Jewish, Christian, or Muslim.