If someone gets heated about something, they get angry and excited about it. You will understand that people get a bit heated about issues such as these + heatedly heat·ed·ly The crowd continued to argue heatedly about the best way to tackle the problem
made warm or hot (`het' is a dialectal variant of `heated'); "a heated swimming pool"; "wiped his heated-up face with a large bandana"; "he was all het up and sweaty"
A heated discussion or quarrel is one where the people involved are angry and excited. It was a very heated argument and they were shouting at each other calm