a sleeveless jacket of buoyant or inflatable construction, for supporting the wearer in deep water and preventing drowning.
Origin of life jacket
First recorded in 1865–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
an inflatable sleeveless jacket worn to keep a person afloat when in danger of drowning
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