booster bag
n.— «During the raids, police seized booster bags worn under women’s dresses to conceal goods shoplifted from stores. “They could get articles as large as fur coats, video recorders, computers, fax machines, 20-piece bone china sets—right under the skirt and out the door.”» —“39 arrested in joint probe of inter-city theft ring” by Henry Stancu Toronto Star (Can.) July 12, 1989. (source: Double-Tongued Dictionary)