na-adjective, noun
infuriating; extremely irritating; galling
Describes a strong feeling of anger or resentment, often at a situation or someone's behavior. Used as a na-adjective or noun.
彼の無責任な態度が業腹だ。
His irresponsible attitude is infuriating.
あの時のことを思い出すと、今でも業腹でならない。
Even now, I can't help feeling extremely irritated when I recall that incident.
Compound of 業 (ごう, 'karma; deed') and 腹 (はら, 'belly; mind'). The exact derivation is uncertain, but it likely expresses the idea of anger welling up from one's karmic disposition or deep inside.