Etimology
From Middle French national, corresponding to nation + -al.
adjective
national (comparative more national, superlative most national)
Pertaining to a nation or country, especially as a whole; affecting, shared by, or existing throughout all of a nation. [from 16th c.]
Belonging to or characteristic of a specific nation or country, as opposed to others. [from 17th c.]
(now rare) Nationalistic; patriotic. [from 17th c.]
Examples
a national assembly · on the front page of every national newspaper
Import tariffs were raised for the national interest.
this is their national dish · our national tendency to laugh at the French
‘Come, come, don't deny it: they are really national. Why, now, the Adams are as liberal-minded men as any in the world: but, I don't know how it is, all their workmen are Scotch.’
noun
national (plural nationals)
A subject of a nation.
(usually in the plural) A tournament in which participants from all over the nation compete.
(usually in the plural, journalism) A national newspaper.
Examples
The diplomats were advised not to interact with any foreign nationals except on official duty.
After winning the regional tournament, the team advanced to the nationals.
I had a crush on Bardot / Fell in love with Monroe / Read about 'em in the nationals / All the juicy little scandals