A self-evident axiom or premise; a pithy expression of a general principle or rule. (noun)
A precept; a succinct statement or observation of a rule of conduct or moral teaching. (noun)
Examples of word maxim
This maxim is a wise guide to a great and simple precaution in life: Never, ever, think about something else when you should be thinking about the power of incentives …
 this maxim is as true as ever fell from poetical pen & there has more morality distilled from the waters of Helicon  than ever was procured from the withered skulls of metaphysicians or Philosophers.
And the old ‘first impressions’ maxim is one which cuts both ways, unfortunately for all concerned.
This is going to be awesome. anthony gadberry just read about this kid in maxim i think ... interesting story.
Yes, because they completely misunderstood what the beer-before-liquor maxim is about.