Balloobs are 2 balloons that are stuffed into someone's shirt and positioned side by side at chest level in order to resemble boobs.
by TrigunBebopLover October 18, 2011
Breasts large enough to resemble balloons, i.e. larger than normal bra sizes. Generally associated with people of the fat variety, though not always.
by lolcatcatlol February 09, 2010