Bio-molecular warhead
From Memory Alpha, the free Star Trek reference.
Bio-molecular warheads were a type of ship-mounted nanoprobe weapon.
This type of nanoprobe weapon was designed in 2374 by Captain Kathryn Janeway and Lieutenant Tuvok of the USS Voyager, in collaboration with the Borg Collective, as a modification to the Starfleet photon torpedo design. Photon torpedoes were encased with Borg nanoprobes to be dispersed upon detonation along with the shock wave to the target vessels.
The bio-molecular warhead proved to be the only effective weapon against the organic technology of Species 8472. A normal class-6 warhead could destroy a single Species 8472 bioship with one hit, while a class-10 photon torpedo had a high-yield warhead with large enough blast area to destroy a squadron of at least thirteen bioships. The smaller warheads had a time delay of several seconds until the nanoprobes took effect. (VOY: "Scorpion, Part II")
Over a year later, in 2375, as a sign of good faith Captain Janeway shared the design schematics of these bio-molecular weapons to Species 8472. In exchange Species 8472 shared technologies used in their terraspheres. (VOY: "In the Flesh")
