The sentence "Sie bieten Arroganz und Anmaßung die Stirn mit aufsässiger Demut." is provided as a usage example of 'Anmaßung' at https://en.langenscheidt.com/german-english/anmassung and is translated into English there as "They stand up to arrogance and hubris with defiant humility."
I am baffled by the presence of "die Stirn" (the 'brow' or 'forehead') in the German sentence. What is it doing there? Would the meaning of the sentence be the same without "die Stirn"? Also, what part of speech is it and what case does it have?