The overhead closure of a room.
The highest altitude at which an aircraft can safely maintain flight.
The overhead interior surface that covers the upper limits of a room.
The smallest integer greater than or equal to a given number.
The upper limit of an object or action.
The measurement of visible distance from ground or sea level to an overcast cloud cover; under a clear sky, the ceiling measurement is identified as "unlimited."
The inner planking of a vessel.
The maximum permitted level in a financial transaction.
A ventilated compartment in which chemical procedures may be undertaken without the escape of noxious fumes into the local environment.