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1. A crease on the palm; its length is said by palmists to indicate how long you will live
   - line of life, life line
    
2. Support that enables people to survive or to continue doing something (often by providing an essential connection)
   "the airlift provided a lifeline for Berlin"; "she offered me a lifeline in my time of grief"
    
3. Line that raises or lowers a deep-sea diver
    
4. Line thrown from a vessel that people can cling to in order to save themselves from drowning

Derived forms: life lines, lifelines

Type of: crease, crinkle, furrow, line, seam, support, wrinkle

Encyclopedia: Lifeline