The Collaborative International Dictionary of English v.0.48:

Life \Life\ (l[imac]f), n.; pl. Lives (l[imac]vz). [AS.
   l[imac]f; akin to D. lijf body, G. leib body, MHG. l[imac]p
   life, body, OHG. l[imac]b life, Icel. l[imac]f, life, body,
   Sw. lif, Dan. liv, and E. live, v. [root]119. See Live, and
   cf. Alive.]
   1. The state of being which begins with generation, birth, or
      germination, and ends with death; also, the time during
      which this state continues; that state of an animal or
      plant in which all or any of its organs are capable of
      performing all or any of their functions; -- used of all
      animal and vegetable organisms.
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   2. Of human beings: The union of the soul and body; also, the
      duration of their union; sometimes, the deathless quality
      or existence of the soul; as, man is a creature having an
      immortal life.
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            She shows a body rather than a life.  --Shak.
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   3. (Philos.) The potential principle, or force, by which the
      organs of animals and plants are started and continued in
      the performance of their several and cooperative
      functions; the vital force, whether regarded as physical
      or spiritual.
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   4. Figuratively: The potential or animating principle, also,
      the period of duration, of anything that is conceived of
      as resembling a natural organism in structure or
      functions; as, the life of a state, a machine, or a book;
      authority is the life of government.
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   5. A certain way or manner of living with respect to
      conditions, circumstances, character, conduct, occupation,
      etc.; hence, human affairs; also, lives, considered
      collectively, as a distinct class or type; as, low life; a
      good or evil life; the life of Indians, or of miners.
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            That which before us lies in daily life. --Milton.
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            By experience of life abroad in the world. --Ascham.
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            Lives of great men all remind us
            We can make our lives sublime.        --Longfellow.
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            'T is from high life high characters are drawn.
                                                  --Pope
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   6. Animation; spirit; vivacity; vigor; energy.
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            No notion of life and fire in fancy and in words.
                                                  --Felton.
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            That gives thy gestures grace and life.
                                                  --Wordsworth.
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   7. That which imparts or excites spirit or vigor; that upon
      which enjoyment or success depends; as, he was the life of
      the company, or of the enterprise.
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   8. The living or actual form, person, thing, or state; as, a
      picture or a description from, the life.
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   9. A person; a living being, usually a human being; as, many
      lives were sacrificed.
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   10. The system of animal nature; animals in general, or
       considered collectively.
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             Full nature swarms with life.        --Thomson.
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   11. An essential constituent of life, esp: the blood.
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             The words that I speak unto you . . . they are
             life.                                --John vi. 63.
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             The warm life came issuing through the wound.
                                                  --Pope
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   12. A history of the acts and events of a life; a biography;
       as, Johnson wrote the life of Milton.
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   13. Enjoyment in the right use of the powers; especially, a
       spiritual existence; happiness in the favor of God;
       heavenly felicity.
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   14. Something dear to one as one's existence; a darling; --
       used as a term of endearment.
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   Note: Life forms the first part of many compounds, for the
         most part of obvious meaning; as, life-giving,
         life-sustaining, etc.
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   Life annuity, an annuity payable during one's life.

   Life arrow, Life rocket, Life shot, an arrow, rocket,
      or shot, for carrying an attached line to a vessel in
      distress in order to save life.

   Life assurance. See Life insurance, below.

   Life buoy. See Buoy.

   Life car, a water-tight boat or box, traveling on a line
      from a wrecked vessel to the shore. In it person are
      hauled through the waves and surf.

   Life drop, a drop of vital blood. --Byron.

   Life estate (Law), an estate which is held during the term
      of some certain person's life, but does not pass by
      inheritance.

   Life everlasting (Bot.), a plant with white or yellow
      persistent scales about the heads of the flowers, as
      Antennaria, and Gnaphalium; cudweed.

   Life of an execution (Law), the period when an execution is
      in force, or before it expires.

   Life guard. (Mil.) See under Guard.

   Life insurance, the act or system of insuring against
      death; a contract by which the insurer undertakes, in
      consideration of the payment of a premium (usually at
      stated periods), to pay a stipulated sum in the event of
      the death of the insured or of a third person in whose
      life the insured has an interest.

   Life interest, an estate or interest which lasts during
      one's life, or the life of another person, but does not
      pass by inheritance.

   Life land (Law), land held by lease for the term of a life
      or lives.

   Life line.
       (a) (Naut.) A line along any part of a vessel for the
           security of sailors.
       (b) A line attached to a life boat, or to any life saving
           apparatus, to be grasped by a person in the water.

   Life rate, rate of premium for insuring a life.

   Life rent, the rent of a life estate; rent or property to
      which one is entitled during one's life.

   Life school, a school for artists in which they model,
      paint, or draw from living models.

   Lifetable, a table showing the probability of life at
      different ages.

   To lose one's life, to die.

   To seek the life of, to seek to kill.

   To the life, so as closely to resemble the living person or
      the subject; as, the portrait was drawn to the life.
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The Collaborative International Dictionary of English v.0.48:

Buoy \Buoy\ (bwoi or boi; 277), n. [D. boei buoy, fetter, fr.
   OF. boie, buie, chain, fetter, F. bou['e]e a buoy, from L.
   boia. "Boiae genus vinculorum tam ferreae quam ligneae."
   --Festus. So called because chained to its place.] (Naut.)
   A float; esp. a floating object moored to the bottom, to mark
   a channel or to point out the position of something beneath
   the water, as an anchor, shoal, rock, etc.
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   Anchor buoy, a buoy attached to, or marking the position
      of, an anchor.

   Bell buoy, a large buoy on which a bell is mounted, to be
      rung by the motion of the waves.

   Breeches buoy. See under Breeches.

   Cable buoy, an empty cask employed to buoy up the cable in
      rocky anchorage.

   Can buoy, a hollow buoy made of sheet or boiler iron,
      usually conical or pear-shaped.

   Life buoy, a float intended to support persons who have
      fallen into the water, until a boat can be dispatched to
      save them.

   Nut buoy or Nun buoy, a buoy large in the middle, and
      tapering nearly to a point at each end.

   To stream the buoy, to let the anchor buoy fall by the
      ship's side into the water, before letting go the anchor.


   Whistling buoy, a buoy fitted with a whistle that is blown
      by the action of the waves.
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WordNet (r) 3.0 (2006):

life buoy
    n 1: a life preserver in the form of a ring of buoyant material
         [syn: life buoy, lifesaver, life belt, life ring]