That dynamic, unique, juggling, complex motion of boobs as a woman jumps, jogs, or walks. The word saves people from saying 'movement of boobs', a rather awkward phrase that usually needs awkward hand motion to get your point across in public.
ex)
A: Do you remember the boobement of Angelina Jolie at the end of Tomb Raider?
B: Yeah, but I personally think the boobement of Pamela on Baywatch had more impact on the general audience.
The town; Belmont, Massachusetts notorious for its drinking problems amung its middle to upper middle class kids in high school. The word always properly defined the town but came to use after an anual luau dance in which the fire departments from several local communites came to assist students to the hospital.