The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- HolisticArrangement (4 members)
- PhysicalConstant (3 members)
- StateOfMatter (2 members)
- Event (1 member)
- PostTransitionMetalElementalSubstance (8 members)
- Charge-discharge cycling (0 members)
- CurrentTimePlot (0 members)
- CurrentPotentialPlot (1 member)
- 3-Point Bending Test (0 members)
- ThreeElectrodeCell (0 members)
- NickelHydroxide (0 members)
- DimethoxyDimethylSilane (0 members)
- Homogeneity wet film (0 members)
- AngularWavenumber (1 member)
- Post-mortem analysis (0 members)
- JosephsonConstant (0 members)
- MagnesiumIodide (0 members)
- MolePerSquareMetre (0 members)
- MaximumContinuousDischargingCurrent (0 members)
- PureNumberQuantity (20 members)
- ElectrochemicallyActiveSurfaceArea (0 members)
- SampleExtraction (1 member)
- Pseudocumeme (0 members)
- IntentionalAgency (9 members)
- HexaFluoroArsenate (0 members)
- EthylMethylCarbonate (0 members)
- MilliMolePerMole (0 members)
- R712 (0 members)
- SurfaceBC3 (0 members)
- CalciumTetrafluoroborate (0 members)
- PerMilliMetre (0 members)
- MesoxalicAcid (0 members)
- LithiumNickelManganeseOxideLithiumIronPhosphateElectrode (0 members)
- MassRatioOfWaterToDryMatter (0 members)
- P20100141 (0 members)
- JoulePerKilogramKelvinCubicMetre (0 members)
- Voltammogram (0 members)
- GasDiffusionElectrode (3 members)
- EdgeInsulator (0 members)
- Redundant (2 members)
- Gravimetric Method (0 members)
- Pressing (3 members)
- Iridium (0 members)
- BatteryCyclerSystem (0 members)
- MercuryAtom (0 members)
- MilliBecquerelPerKilogram (0 members)
- Substance (4 members)
- ConductometricTitration (0 members)
- VolumePerAmountTimeUnit (1 member)
- CobaltSaltCompound (17 members)