noun. A microscopic robot built from nanoscale components, typically 0.1 to 10 micrometers in length.

noun. A very small autonomous robot, typically the size of a biological cell, designed to work alone or in very large numbers to achieve some task. Not yet in practical use.

"Duke (Channing Tatum) and Ripcord (Marlon Wayans) are entrusted with delivering a new 'nanobot' weapon created by arms merchant McCullen (a terrifically scenery-chewing Christopher Eccleston)."

grey goo  

Malayan  bacillary  beaten-down  busted-up  disperse