also: ちゅっぱら
suppressed anger; pent-up irritation; simmering rage
Describes anger that is held in check, not openly expressed. Often used when someone is clearly annoyed but trying to stay composed.
He stayed silent, looking like he was holding back anger.
I was simmering with anger at my boss's unreasonable order, but I couldn't say anything.
He got inwardly angry and left the room without saying a word.
She attended the meeting while holding in her simmering irritation.