When breasts, of any size, or shape, or color or species, look so soft and inviting that one would wish to lay on, in, or between for purposes of napping. Those breasts would be flublacious. or full of Flublaciousness.
A thing that is large and/or jiggly. This word is usually used when referring to a character drawn disproportionately, or when referring to a large/jiggly body part.