Definitions
1.NounA lifesaver: a rescuer, usually an expert swimmer, employed to save swimmers in trouble or near drowning at a body of water.
2.NounA bodyguard or unit of bodyguards, a guard of someone's (especially a king's) life or person.
3.NounA sturdy metal bracket fixed in front of each of the leading wheels of a train to deflect small objects away from the wheels to prevent derailment.