A firearm- Usually a handgun or revolver. This term came from the 30's mafia/gangster times. When continually fired, the barrel would get very warm- hence the name heater.
"Before we go out tonight, do you got your heater?"
Don't mess with her, she's got a heater.
By Cristabel
On A Heater
An extreme hot streak in a poker game or casino game. To become very hot in some form of gambling, profit, or accomplishment. To be at the top of your game.
I was down to my last 20 dollars in the slot machine and then I went on a heater. I was on a heater last night at the craps table, I made a lot of money!
Gambling term refers to winning lots of money in a short period of time. Heater(s) means 4 or 5 digit wins or payouts gambling in a few days or a few weeks.
Last week I went on one of my insane heatersplaying poker online. I started with $200 and worked it up to $3500 in 3 days playing No Limit Holdem.