Fireballs rhymes with:
butterballs, basketball's, basketballs, butterballs, eyeballs, fastballs, football's, footballs, handballs, meatballs, mothballs, oddballs, snowball's, snowballs, softballs, spaceballs, spitball's, trackballs
Fireballs sounds like:
fireflies, fireplace, fireplaces, frivolous