a streamlined metal housing or removable covering for an engine, especially an aircraft engine, often part of or forming a continuous line with the fuselage or wing.
Old English cugele, from Late Latin cuculla cowl, from Latin cucullus covering, cap, hood
Word Origin and History for cowling
cowl
n.
Old English cule, from earlier cugele, from Late Latin cuculla "monk's cowl," variant of Latin cucullus "hood, cowl," of uncertain origin. Cowling is 1917 in the aircraft sense.