noun an aerial manouvre performed off a diving board involving making first contact with the
water surface with the buttocks, or a
single piece of buttock. The bummy results in a imposing display of man and
water that onlookers will find awe inspiring and will create a sonic boom so powerful it has bee known to blast bikini tops off nearby BummyHo's.
It is also polite and acceptable to enquire after witnessing a bummy how many pairs of shorts the bummy artist was wearing before you dive in.
Not to be confused with an old man who writes books under the pseudonym 'Bummy'