What it means
Means letting out stress, anger, or bottled-up frustration so it doesn't keep rattling round your head. You might do it with a rant, a run, a gym session, loud music, or even a long stomp outside. It's a super common everyday phrase when someone's tense and needs a pressure release before they properly lose it.
Usage examples
"After that meeting I was fuming, so I hit the gym to blow off steam, then grabbed a kebab and calmed right down."
"After a brutal week she goes for a long run to blow off steam."
"Let him rant for five minutes, he just needs to blow off steam."
"I had to go for a drive after that call just to blow off steam before I said something stupid."
"He's not mad at you, he's just blowing off steam after a proper nightmare of a shift."
Where it comes from
It comes from steam engines and boilers. When too much pressure builds up, steam has to be released so the whole thing doesn't burst. English carried that image over to people, so blowing off steam means letting stress or anger out in a safer, more manageable way.
