To dunk ones scrotum into the open mouth of another person while facing away from them. Reverse Teabag.
Victoria loves to be moonbagged as it gives her plenty of access to the buttclit.
by angiesunderfire March 03, 2015
Something that is a great distance away, as a bag on the moon is from any point on Earth.
John's farm in rural Virginia is a moonbag down 66 from Washington, D.C.
by JLBSBGP January 06, 2011