It stands for LAWS. These are the lethal autonomous weapon systems, also called killer robots. Far from being futuristic hallucinations of science fiction writers, they constitute one of the nuclei of the current arms race.
The US is conducting an aggressive plan to develop different types of semi-autonomous and autonomous weaponry, conducting both basic and applied research. Among the central aspects are the improvement of perception, reasoning and intelligence of machines but also the collaborative interactions between machines and humans.
As an example, one of the main programs – conducted by DARPA (Defense Advanced Research Projects Agency) – is OFFSET (OFFensive Swarm-Enabled Tactics), which aims at the integration of drone smart drones with ground robots and small infantry units to operate in urban contexts.