(Australian/English slang)
Uncircumcised penis, i.e. intact with the foreskin concealing the
glans, which to some, strangely resembles the soft,
crumpled woolen headwear!
Antonym: Helmet
When I was at high school, we'd play
handball and often separate into different teams using physical aspects, such as light hair vs. dark,
talls vs. shorts and of course,
beanies vs. helmets!