Cubic millimeter
A cubic millimeter (mm3) was a unit of  defined as a cube measuring one millimeter on each side. One cubic millimeter was equal to one microliter.

When The Doctor learned that  was investigating a nebula in 2371, he complained to B'Elanna Torres, "That's all we do around here. Why pretend we're going home at all? All we're going to do is investigate every cubic millimeter of this quadrant, aren't we?" ()

Comparative list of volumes 
 2 cubic millimeters: A remat detonator was typically no more than two cubic millimeters in size, meaning it could be hidden in an article clothing or injected into the skin. ()

 3 cubic millimeters: The explosive that went off aboard K'mpec's attack cruiser was determined to be made from a triceron derivative, and was believed to have not been any more that three cubic millimeters in size, meaning it could have been hidden anywhere in K'mpec's chamber. ()

 25 microliters: Tom Paris attempted to save the life of Ahni Jetal by giving her a twenty-five microliter dose of acetylcholine, however, it didn't help, and she began undergoing massive synaptic failure. ()

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Medical measurements
Measurements