inertimasse
Inertimasse is a fictional substance described in the science fiction novel "A Fire Upon the Deep" by Vernor Vinge. It is depicted as a material that possesses a unique property: it can absorb and store kinetic energy. This absorption is a natural, inherent characteristic of the substance. When subjected to motion or impact, inertimasse does not react with elastic rebound or dissipation of energy in the typical ways other materials do. Instead, it effectively becomes "heavier" or more resistant to further change in its state of motion as it accumulates kinetic energy.
The primary application of inertimasse in the novel is for creating incredibly durable and powerful weaponry