To delete a space in Cyn.in, simply navigate to the contents view of the Space above it and delete the space.

E.g. you have space structure like this

Home
Space A
Space B
        Space C
        Space D
Space E

To delete Space C, go to the "Manage Space: Contents" view of the Space B. Space C will be listed as a folder there. Select the space with the checkbox next to it and hit the delete button at the bottom of the table.

* The Manage Contents view is available only to Editors of the Space.

Hope this helps.

Got it! I didn't click that Home is actually "above" Space A, so that to delete Space A I can go to the contents view of Home.

Just a feedback comment here, I was unable to delete a space under the following scenario. I will continue using the sample structure used by Romasha.
1. I wanted to delete Space C, but I first deleted some files that were into Space C.
2. After deleted some files, I went to Space B and I tried to delete Space C, but I got a message saying that Space C was not deleted.
3. So that, in order to delete Space C, I want to the "Recycle Bin" at the Administration section and I deleted the files that were on Space C.
4. After deleting the files from the "Recycle Bin" I was able to delete Space C from the "Manage Space: Contents" view of Space B.

I hope this could be useful for someone... cheers!