That's how you say "hello" in Egyptian Arabic, which adds yet another greeting to Fiorella's ever-growing repertoire. She learned it from the golden-haired clerk who checked her out in H-E-B a couple of days ago, then solidified it in her brain by repeating it to the woman yesterday when Fio realized she'd wound up in the same register line.
Where did Fio's fascination with languages come from? Maybe from the early exposure Fio has previously described--her great aunts and uncles teaching her a "soft Russian" phrase ("God, give health") to use when she sneezed, maybe from a Louisiana-born neighbor teaching her to say "I love you" in French, another neighbor teaching her hose to count to ten in Spanish, her mother teaching her how to count and recite the alphabet in German. Maybe from moving from Ohio to Texas and having to learn a whole new version of English. Maybe from her desire to communicate with everyone she meets, or from her own weird brain, which seems to be attracted to unraveling intricacies.
Whatever, Fiorella is hooked. The next time she goes through Goldie's line, she'll ask her how to say "thank you."