a spoiler mounted at the front of an automobile to reduce air flow on the underside of the chassis to increase stability.
Origin of air dam
First recorded in 1970–75
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for air dam
any device, such as a spoiler, that reduces air resistance and increases the stability of a car, aircraft, etc
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012