This is the 2997th most frequent Swedish word.
heta
"To be called/named" or "to be hot."
In this sentence, 'heter' is used to indicate someone's name or what they are called.
Mitt namn är Erik och jag heter Erik.
My name is Erik and I am called Erik.
Here, 'heta till' is used to mean an increase in temperature, becoming heated physically.
Det här rummet kommer att hetta till när solen ligger på.
This room will heat up when the sun shines on it.
In this case, 'heta till' is metaphorically describing intensification or escalation in an argument.