steaming
adj.extremely angry or very hot. You use this to describe someone who is so mad that they look like they might have steam coming out of their ears.
adj.experiencing or expressing intense anger; also used to describe something emitting water vapour due to high temperature. Often used predicatively after 'be' or 'get'.
“He was absolutely steaming after the meeting.”
“She was steaming when she found out that her flight had been cancelled without any prior notice.”
“The manager was visibly steaming as he walked out of the press conference, refusing to answer any further questions about the team's recent performance.”
Often modified by 'absolutely' or 'visibly' to emphasise the intensity of the emotion.
“Steaming hot liquid can damage the cell lining on the way down to the stomach, experts say.”
By surface analysis, steam + -ing.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.