"Central to the Reach's plans were the Scarabs, a hive-mind native to Space Sector 2. The Scarabs were living weapons, genetically engineered by the Reach and programmed to be obedient to them."
~Wiki

Also it the one bounded ot Jaime for example is sentient, symbiotic as it's bonded with him and can't move much on it's own. So... I'd say organic robot. Something along the lines of inbetween. It can learn and stuff... So yeah.