Current sources of accommodation? (5)

I believe the answer is:

cells

I'm a little stuck... Click here to teach me more about this clue!

But I can't explain it at all! Could you help me understand?

(Other definitions for cells that I've seen before include "Basic structural units of all organisms" , "Dungeons" , "terrorist groups" , "Accommodation for prisoners" , "Rooms for prisoners" .)

Want a hint initially instead of a full solution? Install my app