The most common and most likely answer to this crossword clue is the 6 letter word SOMALI
I've seen this crossword clue in The Daily Telegraph
S
O
M
A
L
I
More clues leading to the result SOMALI
- Really, place in Africa is African
- Thus one African country identifies an inhabitant of another
- Old woman borne by short strong African
- Note on West African country’s language
- Very African country? Not this person’s
- Note African country – and one from another
- African, like that country
- African country like that leads
- African, very African country
- African sots maligned, both half-cut
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 = somali.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.