@oristarA,
No, that doesn't properly explain the word. I hate it when they use the word in the definition of the word!
My favorite online dictionary is rhymezone.com. It's a great resource for people learning English. You can look up more than rhymes -- synonyms, antonyms, related words, definitions, homophones, even Shakespeare quotes!
It gives the same definition you've found for "pert" but under synonyms it says:
Quote:Words and phrases that can mean the same thing as pert: (4 results)
impertinent, irreverent, saucy, spirited
Each of they synonyms is a link to the definition of that word so it can help you get a better understanding of what each word means.
If you haven't used rhymezone it is worth investigating!