The small orgasm that you get when you play minecraft and you find a shit-load of coal.say if you find a 20x20 wall and it is covered with coal. Also can be used with lavagasm, goldasm, and irongasm.
Person 1 " hey, if you find any co....coal? COAL???? COALLLL!!!
Person 2 "hey are you alright?"
Person 1 "yea, i just had a major coalgasm.