1. an anchored line or rope thrown to support a person in danger of drowning or falling.
2. a safety line strung along the deck of a ship as a handhold in stormy weather.
3. the line used to raise and lower a diver.
4. the only available route or means by which necessary or vital supplies can be transported.
5. a source of or means to what is vital for survival or continuance.
example: “In good conscience, we cannot let another year pass without extending to all seniors the lifeline of affordable prescription drugs.”
6. in palmistry, a curved line at the base of the thumb that reveals information about a person’s life.