Submicroscopic robots originally designed to perform medical functions within the bloodstream of a living organism.

Such functions could encompass intracellular surgery, eliminating individual disease cells, or removing clotted material from a blood vessel, and more.

Manufactured with gigabytes of mechanical computer memory in Dakar, Senegal, nanites were designed for inner-nuclei exposure only during cellular surgeries, and were therefore kept in a nonfunctional state when not in use.

While onboard the U.S.S. Enterprise NCC-1701-D in 2366, Acting Ensign Wesley Crusher was conducting experiments in nanite interaction when his subjects suddenly went awry, resulting in the creation of sentient and self-replicating nanites. During their early explorations, the newly developed nanites interfered with vessels onboard systems which jeopardized a landmark astrophysics experiment being conducted by Doctor Paul Stubbs. Several developing nanites were unwittingly destroyed before being recognized as sentient life-forms. Once the level of their development was discovered, however, the nanites were willing to negotiate, and were finally granted colonization rights to planet Kavis Alpha IV.

Nanites programmed for destructive purposes were also briefly considered by U.S.S. Enterprise NCC-1701-D personnel as a possible defense during the Borg offensive of 2367. This plan was abandoned due to the length of time required for the nanites to have an effect, which would have been weeks after the Borg attack of planet Earth.