The Collaborative International Dictionary of English v.0.48:
Bomber jacket \Bom"ber jack`et\, n. [From its resemblance to the style of jacket work by the crews of World War II bomber airplanes.] a short men's jacket made of leather, having a zipper in front, knitted cuffs, and ribbed trim. [PJC]WordNet (r) 3.0 (2006):
bomber jacket n 1: a jacket gathered into a band at the waist