The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- AreaFractionUnit (0 members)
- RichardsonConstant (0 members)
- SemioticObject (0 members)
- TimePerVolumeDimension (0 members)
- QuantumData (0 members)
- Chlorine (0 members)
- SemanticStatement (0 members)
- GoldElectrode (0 members)
- SecondAxialMomentOfArea (0 members)
- OrganicCompound (0 members)
- VC (0 members)
- TennessineAtom (0 members)
- SICoherentUnit (0 members)
- ArithmeticOperator (0 members)
- MeasurementProcess (0 members)
- Field (0 members)
- LeadSymbol (0 members)
- EnergyDensityOfStates (0 members)
- IronSymbol (0 members)
- GalliumAtom (0 members)
- ContinuumManufacturing (0 members)
- DarmastadtiumSymbol (0 members)
- CurrentChangeLimit (0 members)
- DerivedQuantity (0 members)
- SurfaceActivityDensity (0 members)
- DiffusivityDimension (0 members)
- LinkedFlux (0 members)
- KryptonAtom (0 members)
- IonicStrength (0 members)
- AngularReciprocalLatticeVector (0 members)
- Coded (0 members)
- Chronoamperometry (0 members)
- MixingSpeed (0 members)
- Quark (0 members)
- FabricatedSecondaryElectrochemicalCell (0 members)
- YttriumAtom (0 members)
- ElectricCurrentPerMassDimension (0 members)
- PromethiumAtom (0 members)
- InitialDischargeVoltage (0 members)
- DirectionDistributionOfCrossSection (0 members)
- Kilo (0 members)
- LeadAtom (0 members)
- MagneticPolarisation (0 members)
- Numeral (0 members)
- DebyeTemperature (0 members)
- SwagelokCell (0 members)
- Battery (0 members)
- PouchFoil (0 members)
- YttriumSymbol (0 members)
- Liquid (0 members)