Term: Lifeline Image: [{"name":"images\/public\/dictionary\/Lifeline_dzt6faex.jpg","usrName":"Lifeline.jpg","size":60774,"type":"image\/jpeg","thumbnail":"images\/public\/dictionary\/thLifeline_a2tbu4v0.jpg","thumbnail_type":"image\/jpeg","thumbnail_size":60774,"searchStr":"Lifeline.jpg,!:sStrEnd"}] Definition: Safety lines on deck that are grabbed to prevent falling overboard.