Of critical importance to the survival of a living organism. / Having death as a possible or even likely outcome; perilous. / Of critical importance to the success of a particular endeavor.

An account of an individual's life / (by extension) A long detailed monologue to someone

(rare) To help someone achieve their personal goals.

A professional who helps clients to achieve their personal goals.

plural of life expectancy

(law) The recipient of a life estate.

plural of life tenant

The aspects of social life which occur in public, in the open, as opposed to more private social interaction within families, private clubs, etc. / Politics, as in the profession of being a politician.

plural of life partner

plural of life ring