When
someone gets so mad that it has the potential to ruin their whole
day. Noticeable when
someone lets their anger leak out, usually described in forms of yelling or raising their voice in defense.
When I told josh I screwed his girlfriend he maxed out.
"
Dude are you serious? I can't believe you, out of all people, got me to
max out."
"What?!?! I got an F on my Spanish exam? My parents are going to
max out!!"