dack dack
A wobbly or strong penis, or the act of having sex, and it's usually said when people are being loud or stupid.
They shouted 'dack dack' during the movie and ruined it for everyone.
I said 'dack dack' when I failed my test and got a zero.
My neighbor yelled 'dack dack' at 2 a. m. and I was mad.