A martin is a similar version of a boomer except he is about 10 times stupider than a boomer.
A martin is a man who thinks he knows everything and always talks big.
A Martin is the act of taking a shitin the shower and forcing it down the plug hole with your toes. Often used as a treat to celebrate a good day at school or a promotion at work etc
'Hi John, how's your day been?' 'Yeah not too bad thanks, I finally got that pay rise at work. I'm just heading home to have a celebratory beer and a Martin!'