Regarding the etymology of the word, it is most likely another anglified French word, from the original "savoir," which means "to know." Like parley (also used in "Pirates"), which means "to speak," it was probably absorbed into the English vocabulary back when French was more of a global language.
She's such a savvy dresser.
Now used by PotC fans to mean, "Get it?"
"OMG Ellen, thoose shoes are savvy!"
"The Johnny Depp club is so savvy"