Lifeline

Noun

 * 1) A line to which a drowning or falling victim may cling to.
 * 2) A means or route for transporting indispensable supplies.
 * 3) A source of salvation in a crisis.
 * 4)  On the deck of a boat, a line into which one can attach himself to stay aboard on rough seas

Thesaurus
Mae West, aegis, arm guard, backstop, bolt-hole, breeches buoy, buffer, bulwark, bumper, buoy, contraceptive, copyright, cork jacket, crash helmet, cushion, dashboard, dodger, ejection capsule, ejection seat, ejector seat, emergency exit, escape hatch, face mask, fender, finger guard, fire escape, foot guard, fuse, goggles, governor, guard, guardrail, hand guard, handrail, hard hat, helmet, inflatable slide, insulation, interlock, knee guard, knuckle guard, laminated glass, life belt, life buoy, life jacket, life net, life preserver, life raft, life ring, life vest, lifeboat, lightning conductor, lightning rod, mask, mudguard, nose guard, pad, padding, palladium, parachute, patent, pilot, preventive, prophylactic, protective clothing, protective umbrella, rubber dinghy, safeguard, safety, safety belt, safety glass, safety plug, safety rail, safety shoes, safety switch, safety valve, sally port, screen, seat belt, shield, shin guard, slide, sun helmet, umbrella, water wings, windscreen, windshield

Alternative forms

 * life-line
 * life line

Etymology
From life + line.

Pronunciation
līf' līn'

Translations

 * Finnish: elämänlanka