lifelines

noun

1. 1

   A line to which a drowning or falling victim may cling.

2. 2

   (by extension) A source of salvation in a crisis.

3. 3

   A means or route for transporting indispensable supplies.

4. 4

   System or structure of vital importance to a community.

5. 5

   On the deck of a boat, a line to which one can attach oneself to stay aboard on rough seas.

6. 6

   A line from the diver to a tender at the surface control point.

7. 7

   A particular crease in the palm.