Cotton Ceiling Meaning

Example: Used other than as an idiom: see cotton,‎ ceiling.
1872, Mrs. Edward Millett, An Australian Parsonage; Or, The Settler and the Savage, page 56:
  On rough nights, however, the wind that finds its way beneath the rafters keeps drawing up and down the cotton ceiling in sudden gusts, and if the fastenings of your canopy are not very artfully contrived, one end or other of it is sure to give way […]
1933, State of New York Supreme Court Record on Appeal, page 85:
  These ceilings on this house are not a canvas ceiling. They are a cotton ceiling and the water can drop on these ceilings […]
An unwritten social barrier to consideration (by cis people) of transgender people as viable sexual partners.