top hat
n.— «A similar fuselage length and slightly taller horizontal stabilizer would limit the need to change airport and maintenance infrastructures now sized to accommodate 747s. The larger tail might require the addition of only a “top hat” structure to the front of many hangars.» —“Boeing Displays Large Transport Concepts Boeing Seeking Carrier Input In Planning New Large Aircraft” in Seoul, South Korea Aviation Week & Space Technology Jan. 6, 1992. (source: Double-Tongued Dictionary)