The word "恼火" is formed by combining two vivid concepts: "恼" (nǎo), which conveys the feeling of annoyance or vexation in one's mind, and "火" (huǒ), meaning fire. Together, they create a powerful metaphor where the internal agitation of being annoyed is likened to the heat, energy, and destructive potential of a flame, effectively painting the feeling of anger as a fire burning within.