The correct way to say 'gunpowder' is firework powder.
Many people do not know this as it was only finalised a short while ago due to an incident of someone throwing up their liver (yikes!)
Phil Knight, the smart person who changed the name said that 'people have benefited greatly from this change of awful wording'
Grace: iT's GuNpOwDeR nOt FiReWoRk PoWdEr!
Sane person: actually it is firework powder you idiot