A Dalek holding cell was a form of holding cell used by the Daleks.
A Dalek holding cell descends around the Meta-Crisis Tenth Doctor.
Locations which contained holding cells included the Dalek City on Skaro and the Crucible. (DW: The Daleks)
The holding cell appeared to be nothing more than a spotlight in the ceiling. When impacted, the blue energy of the cell was visible. There was some discrepancy in how the holding cell appeared when activated: sometimes, only the light in the ceiling was seen until the cell was impacted and the energy was visible, but on at least one occasion, the forcefield visibly descended when the cell was activated. It is possible that the cell was being impacted as it was descending. (DW: Journey's End)