Technology / Aviation / Ceiling: (1) The heights above the earth's surface of the lowest layer of clouds or obscuring phenomena that is reported as 'broken,' 'overcast,' or 'obscuration,' and not classified as 'thin' or 'partial'. (2) The maximum height above sea level in STANDARD AIR attainable by an aircraft under given conditions—see ABSOLUTE CEILING, SERVICE CEILING.

Ceiling Joist

Business / Construction / Ceiling Joist: One of a series of parallel framing members used to support ceiling loads and supported in turn by larger beams, girders or bearing walls. Also called roof joists. MORE

Variable Ceiling

Science / Weather / Variable Ceiling: Occurs when the height of a ceiling layer increases and decreases rapidly, The ascribed height is the average of all the varying values. MORE

Measured Ceiling

Science / Weather / Measured Ceiling: A ceiling classification applied when the ceiling value has been determined by an instrument, such as a ceilometer or ceiling light, or by the known heights of unobscured portions of objects, other th MORE